Awhile back speeddemon32 tested the Mazdaspeed sport springs and found them to be at a rate that was something like 180/100. http://www.rx8club.com/showpost.php?p=1883212&postcount=100 Of course, the rate that was previously agreed upon here was 280/190 and some people continue to believe that rate. In addition, I e-mailed a vendor and he told me the Mazdaspeed coilover spring rates are 40% stiffer than the sport springs. Since the coilovers are 400/275, 280/190 for the sport springs would make sense. So with so much conflicting information, does anyone actually know what the Mazdaspeed sport springs are?

they were measured on a spring compressor. how do you argue against that?

Since the coilovers are 400/275

Just Wondering where you got those numbers from? I have not seen any published numbers on the coilovers other than about 90% stiffer than stock. This is from the Mazdaspeed catalog as well as Eibach (The manufacturer). I have never seen any official numbers on the Springs either. Based on my calculations:

Stock as tested by speeddemon:
~160 Fronts
~110 Rears

Mazdaspeed as tested by speeddemon:
~180 Fronts
~100 Rears

Mazdaspeed Coilovers (Using 90% up from stock)
~295 Fronts
~205 Rears

These numbers also coincide with what that vendor says about the springs being about 40% less stiff then the coilovers. The rears are a little off on the Coilover calculations as compared to the MS Springs. But I suspect that the coilovers are the 280/190 as stated pretty much everywhere as the rates for the MS Springs.

Just my 2 cents, you can decide for yourself.

Anyone want to buy the coilovers and test my theories? probably not.

Just Wondering where you got those numbers from? I have not seen any published numbers on the coilovers other than about 90% stiffer than stock. This is from the Mazdaspeed catalog as well as Eibach (The manufacturer). I have never seen any official numbers on the Springs either. Based on my calculations:

Stock as tested by speeddemon:
~160 Fronts
~110 Rears

Mazdaspeed as tested by speeddemon:
~180 Fronts
~100 Rears

Mazdaspeed Coilovers (Using 90% up from stock)
~295 Fronts
~205 Rears

These numbers also coincide with what that vendor says about the springs being about 40% less stiff then the coilovers. The rears are a little off on the Coilover calculations as compared to the MS Springs. But I suspect that the coilovers are the 280/190 as stated pretty much everywhere as the rates for the MS Springs.

Just my 2 cents, you can decide for yourself.

Anyone want to buy the coilovers and test my theories? probably not.

My 400/275 number comes from a vendor who e-mailed Mazdaspeed about their coilovers. This vendor (bagman1) is for Online Mazda Parts and is on miata.net. I don't think he's here.

Ok, thanks for the info.

I have to disagree with these #’s
Mazdaspeed as tested by speeddemon:
~180 Fronts
~100 Rears
The reason is that I have the MS springs and the ride after the install was way stiffer and the car felt great on the track. I can’t believe that a 20 increase in the front and 10 decrease in the rear would feel that much different. It has to be more, now how much more I have no idea. All I can say is that from my personal experience they are much stiffer.

I have to disagree with these #’s
Mazdaspeed as tested by speeddemon:
~180 Fronts
~100 Rears
The reason is that I have the MS springs and the ride after the install was way stiffer and the car felt great on the track. I can’t believe that a 20 increase in the front and 10 decrease in the rear would feel that much different. It has to be more, now how much more I have no idea. All I can say is that from my personal experience they are much stiffer.

Could the extra stiffness be attributable to the shocks?

I have to disagree with these #’s
Mazdaspeed as tested by speeddemon:
~180 Fronts
~100 Rears
The reason is that I have the MS springs and the ride after the install was way stiffer and the car felt great on the track. I can’t believe that a 20 increase in the front and 10 decrease in the rear would feel that much different. It has to be more, now how much more I have no idea. All I can say is that from my personal experience they are much stiffer.

Yeah, I have heard many reviews on the springs saying they were much stiffer, I have not tested or used them myself though. I am just posting what speeddemon tested them as. Since he confirmed other spring rates I have no reason not to believe him or his methods of testing.

As far as the shocks making the springs feel stiffer, that could definitely be true. If the mazdaspeed shocks are running much stiffer dampening then that would make everything seem stiffer. BUT, the dampening on the shocks wouldn't have any effect on the actual spring rates. It would NOT actually make the springs stiffer but it can make the entire suspension FEEL stiffer. Just ride in any adjustable shock setup and you will feel the difference between the soft/hard settings, but it doesn't actually change the spring rates.

I just wan't to say that I am not attacking the Mazdaspeed components and I have no doubt that they are quality pieces. Its just that there is so little actually published about them that the only way to come to your own conclusions is to test them yourself which not many people are willing to do.

Could the extra stiffness be attributable to the shocks?

You know what you are right. I forgot all about that part. So in short the MS suspension combo feels great, it may be more then some other combos but they work well together. I would like to know the actual spring rates.

I have heard that the springs were stiffer than stock even from someone running Koni's, which are softer than stock on the softest setting I believe.

I have heard that the springs were stiffer than stock even from someone running Koni's, which are softer than stock on the softest setting I believe.

Koni Yellows are stiffer than stock on all settings.

they were measured on a spring compressor. how do you argue against that?

I'd like to see the technique used

unlike a coilover spring, the OE type springs are not flat on one end

it would take a special sloped perch to be carried out properly ...

My bad. I swear I read that somewhere on here. I really hope someone is able to get a definitive answer on all the mazdaspeed stuff.

I'd like to see the technique used

unlike a coilover spring, the OE type springs are not flat on one end

it would take a special sloped perch to be carried out properly ...

interesting development! How big of a difference in the reading do you think it could make?

How does one go about finding a local place to test spring rates? I have Mazdaspeed sport springs & Tein S-techs in a box... would be interesting to throw them on a tester.

Maybe a speed shop or a suspension shop. Lety us know what you find out.

I am looking at purchasing the MS springs to lower the ride height and eliminate wheel gap a bit. Will I be satisfied. I am purchasing the entire MS kit and with the cost of the springs I thought that would be a good addition as well. I have yet to consider autox which is why I dont think coilovers are a good fit for me at this time. Any suggestions

I'd like to see the technique used

unlike a coilover spring, the OE type springs are not flat on one end

it would take a special sloped perch to be carried out properly ...

My question would be if that were the case, why did the OE spring rates come out exactly where they should be?

My question would be if that were the case, why did the OE spring rates come out exactly where they should be?As well as some random springs with the rates stamped on them...??

I'm just trying to rid some gap as well. Don't AutoX it at all and I've gotten used to the factory ride feel. I would like to keep the factory shocks too. Only 18k on them. Just wanna drop the car an inch....

i like them alot. I will be updating my sig soon ;)

There's no way that the MS springs are softer than stock in the rear. They are pretty damn stiff, I ran a set with my Konis and I thought I was going to jar my teeth out for the first few days. They are progressive rates rather than linear so if you press on them out of the car they do seem initially softer.

speed's family has been involved with racing for years.
he has the means to find out about the springs..

I wonder if perhaps the Mazdaspeed springs are purposely soft in the beginning of the travel to accommodate a ride height. How much travel is in the spring?

You'd have to load a progressive spring to it's compressed ride height dimension before beginning the test to get an accurate indication of it's rate

You'd have to load a progressive spring to it's compressed ride height dimension before beginning the test to get an accurate indiucation of it's rate
Ahhh probably why we have some "false" numbers floating around then....

I tested the stock front spring which we ALL KNOW is 156#'s

I tested the stock rear spring which we ALL KNOW is 113#'s

I tested a 500# spring I have laying around the garage.

I tested a 700# spring I have laying around the garage.

ALL 4 CONTROLL SPRINGS CAME BACK WITH WHAT WAS EXPECTED.

So when I test the Mazdaspeed spring, the sprint spring, the what ever spring you want, I dont know how you can dispute the rates I get back!?!?!?

Yes the perch on the spring rate checker is curved to match the springs. yes I tested more then 1"., in fact on the Mazdaspeed springs I beleive I even posted 3" of measuments.... if I rememember right it progressivly got stiffer by 10#'s per inch.


anyone else not belive the rates...... sorry, your on your own.



EDIT: ah yes, here is the Mazdaspeed spring test (ALL 3 Inches) http://www.rx8club.com/showpost.php?p=1883212&postcount=100

and here are 3" worth for the sprint springs. http://www.rx8club.com/showpost.php?p=1909352&postcount=130

so yes, I did test the progresivness of the springs.

I believe you, which is why I don't have Mazdaspeed.

Thanks :kiss:
he he he.

I just dont see why there is even doubt, thats all. :)

Thanks though!

interesting development! How big of a difference in the reading do you think it could make?



oh yeah, just for Sh*#ts and giggles I tested the springs on both my flat perch, and my curved purch, they came back with t;he same results. its just a matter of what keeps the spring in the tester better. ;)

It's not about not believing your testing methods. I do believe your numbers are obtained accurately. However, car suspensions are designed with several inches of droop and in a situation like the Mazdaspeed sport springs where there are no tender springs, the portion of the suspension that is designed as droop needs to be close to stock rate or else you sacrifice droop travel, which is bad for rough roads. That is why I asked how much travel is in the spring; generally a suspension will have similar amounts of droop and compression travel.

Think about it this way, if you up the spring rate by a factor of 2, you only need half as much travel as what you did to support the weight of the vehicle. If you're shooting for a ride height close to stock, that would mean losing about half your droop travel, a bad situation! Coilovers partially avoid this problem by having a low rate tender spring, but the Mazdaspeed sport spring is a standalone which means the only solution to keeping the needed droop is an aggressive progressive rate, linear or otherwise.

Considering what I've seen of the RX-8's front suspension and assuming a stock rate, there's probably something like 4 inches of droop from static in that setup.

... ummmm ..... ok.

I have no idea what you are getting at.

I measured the entire spring range (with the exception of the first inch, witch is useless information anyways) and all I am trying to say here is that the spring rates I came up with are legit. the Mazdaspeed spring IS progressive, and it is progressive by 10 pounds per inch. (wooptie doooo) meaning if it was a 170 pound spring at the first inch, it was a 180 pound spring at the second inch, and a 190 pound spring at the third inch. nothing close to the 280 pound (or whatever) spring we all thought it was.

when I was looking for a new spring to go with I was looking for the stiffest spring I could find. (quadruple the spring rates would have been nice) with 285 R compound tires and the Koni struts, a super stiff spring would have been nice. but unless you go with a coil over where you can put a real stiff spring on, your just not going to get a stiff replacement spring for the struts on an RX-8.... they just dont exist for this car at this point. (Disclaimer:... none that I know of). they are all very close to the stock rates.

all the replacement lowering springs are exactly that.... lowering springs. which is not a bad thing, it makes the car look good and lowers the center of gravity... just dont expect it to be a stiffer spring by more then just a couple of pounds. :(



the point of my reply to this thread was to backup my test numbers. I was under the impression there were concerns my method was not valid. (though I cant see why if they read my thread) I was simply trying to prove my numbers. sorry if I took that wrong. :)

to answer your main question, When I called Mazdaspeed about the numbers I tested I wanted a replacment set because mine were faulty. Mazdaspeed Motorsports Developments responce was "we do not advertise these springs to be any stiffer then factory, we advertise them as lowering springs" they do not know how we came up with the 280/190 numbers on this forum. I could return them if I want, but they were not faulty springs.

take this info how ever you want it. but I have come to the conclussion going off of what Mazdaspeed said and my own, what I consider 100% valid test results, and you have yourself a Mazdaspeed lowering spring..... LOWERING SPRING.

I measured the entire spring range (with the exception of the first inch, witch is useless information anyways)

There's only 4 inches of travel in the spring?

realistically... yes.

when I tested the springs I had the suckers collapsed way further then it would ever be on the car. the coils were damn near touching each other.

I dont know how to be more clear then I have been. when I test a 500 pound spring, it comes back 500 pounds. when I test a 700 pound spring, it comes back 700 pounds. when I test a 140 pound spring, it comes back 140 pounds. when I test a progressive spring and it comes back progressivly 10 pounds stiffer. when I said I tested the full range, I really could not do another inch. I just dont know how to be more valid or clear then that.

I stand by my claim that my Mazdaspeed springs were as follows:

Front Spring 1
170 lb for the first measurable inch
180 lb for the second inch
180 lb for the third inch

Front Spring 2
170 lb for the first measurable inch
180 lb for the second inch
190 lb for the third inch

Rear spring 1
70 lb for the first measurable inch
100 lb for the second inch
90 lb for the third inch

Rear spring 2
70 lb for the first measurable inch
100 lb for the second inch
90 lb for the third inch

And I stand by my claim that there was nothing more I could have done to ensure I get a more accurate result. I could not have tested another inch, I could not have the stars align better then they were that night.


if anyone still thinks they are stiffer then that with all the info I have given, by all means buy yourself a set of Mazdaspeed springs (or any other spring you might think is stiffer) and enjoy them. :) or have them tested by someone else. ;)

I might have drank too much last night (and i did... damn eagles were suppose to get blown out quickly), but last i checked there is roughly 750lbs of weight sitting on the front tires. If the front MS springs are ~170 lbs/in they would need a little over 4 inches of compression to hold the static weight... and if they have a usable range of 4" of travel they would be basically in coil bind with the car sitting on the floor

...let me look at that again when i'm more sober...

and again... I didnt even bother testing the first inch or so, for one my tester wil not even measure accurately that low (it takes a 100 pounds or so to get started) and 2 do you really care what the spring rate is at inch number one? its going to be weaker then any other inch.

If you would like your springs tested from the moment the spring touches the perch, to the moment the spring coils collide then fine. send me your spring, I will run the test (which I have already done myself and got the same spring rates) and I will give you every inch. even if its a stupid test....

or you are welcome to send your springs off to someone else and let them give you the same results.

are you magically expecting the first inch or two to be way strong? cause they are not. I have to pass inch one and two just to get to the starting point of the test, I get to see the dial move up... trust me, its not stiffer, if anything its weaker.


in my eyes, some of you are disputing undisputable data. I am all for scrutinizing how test are done. I dynoed my RX-8 once and even claim that my results are somewhat inconclusive. (this is another story) but there is nothing in the spring test that is disputable. I think I have shown that time and time again already.
.

If the purpose of this thread, as the title implies, is to get a consensus....I would go with believing the numbers found by Speeddemon32. He and I have done plenty of installs on "lowering" springs on the 8. I agree with his phrasing, and it was supported by Mazdaspeed. Most aftermarket springs are just lowering springs. In general, a review of the available options will demonstrate that most companies are producing springs that lower the car, but maintain a stock ride feel. Most people who lower their vehicle are doing it for cosmetic reasons.

I too fell into the initial trap of the numbers posted on the forum. I thought I was getting the stiffest spring out there for the 8. I was autocrossing my car, and I wanted something stiff. Not wanting to go with a Koni yellow/assorted spring combo...I thought, why not go with the MS setup of matched spring and strut.

Butt dyno results told me the setup was very similar to stock. The strut is slightly stiffer, but the spring rates, as measured...are much like stock.

So, from my own 2 cents....in an effort to add to a consensus.....pick up a stiff strut, and then match it with a spring that gets you the desired ride height....because the spring rates are much the same.

Best bang for the buck appears to be a Tein spring....match that up with a Koni yellow....? or, go coilovers.....

Ghost, who was second to post in this thread had a stiff spring/strut setup with Koni's and Vaughtland springs. He recently removed that setup in favor of a set of JIC coilovers. He asked that Speeddemon32 test the Vaughtland spring....they came back much the same as all the other "lowering" springs...rates very comparable with stock. Conclusion.....the struts was the main reason for the ride "stiffness" (for lack of better word).

When I reported the results to Ghost, his initial reaction was, that the results must be wrong. Take results for what they are worth.....at least they are more reliable than butt dynos.

couldnt have said it better myself. :)

I might have drank too much last night (and i did... damn eagles were suppose to get blown out quickly), but last i checked there is roughly 750lbs of weight sitting on the front tires. If the front MS springs are ~170 lbs/in they would need a little over 4 inches of compression to hold the static weight... and if they have a usable range of 4" of travel they would be basically in coil bind with the car sitting on the floor

...let me look at that again when i'm more sober...

r0tor, what you're forgetting is installation ratio. Though the shock mount on the A-arm on the front is really far out and tends to suggest an IR close to 1, it is also going up at an angle. I'm trying to get a good estimate of what the IR actually is, but I haven't had a chance to get the car on a rack to study the geometry in detail.

they were measured on a spring compressor. how do you argue against that?

...funny, now....given our recent conversation about the spring rates on the Vaughtlands....:)

the reasoning behind my conclusion is because i have done several comparisons myself. my car on full soft with the konis is WAY stiffer then s techs with konis 1 turn up from full soft. same with sprints (unsure what the konis were set to. the only way i see this happening is if my preload got messed up somehow.

... I dont know what to tell you buddy. :) if your one of the ones that feels I must be wrong, then take it how you want it. your welcome to belive what ever you want. your also welcome to listen to your butt dyno all you want. :)

I will stick with hard evidence. :P

RX-8 motion ratios:

front = 0.752

rear = 0.855


I'm sure that Mazda Motorsports can confirm the exact rates for the springs. I was simply curious to know how the information was obtained.

^^^ good info. :)


:) now you know :)

I just read your note in the other thread about MMS not knowing the rates

seems odd, they always had the spec info on anything I ever called for

I just read your note in the other thread about MMS not knowing the rates

seems odd, they always had the spec info on anything I ever called for

Maybe you should call Team, you might have special clout!

thats what I was going to say,... give em a call. i still dont see why everyone insist they are stiff springs when they are not. the rumor numbers on this thread seem to have magically appeared. but by all means, give em a call again and see if they know exactly what the spring rates are. :) (hopefully you get a different guy then I did.)

Do It!

do it.... Do It!..... DO IT! ;-)

lol i LOVE the sig speed

Is that spring on the right the stockers?

ha ha ha, yeah I thought it was fitting for now. ;)



yes the spring on the right is a stocker.

(hopefully you get a different guy then I did.)

Possible, but only four people work there.

r0tor, what you're forgetting is installation ratio. Though the shock mount on the A-arm on the front is really far out and tends to suggest an IR close to 1, it is also going up at an angle. I'm trying to get a good estimate of what the IR actually is, but I haven't had a chance to get the car on a rack to study the geometry in detail.

it still fails to work...

speed...you could always consider changing your new siggy to:

Springs, sometimes they just don't measure up

it still fails to work...

You're right. Assuming 800 pounds per front corner and a 0.752 installation ratio, just to get to static ride height you'd need more than 3.75 inches of travel on a 155 pound spring. There has to be more than 4 inches of travel in that spring...

It looks even worse on rear springs as that requires more than 5 inches of travel to reach static compression.

i dont remember ever once saying that there is only 4 inches of travel.... look guys, its simple, they are what they are. there is no magic inch in there that the spring is ungodly stiff ok. if you think there is, then by all means think what you want.
I give up.


chicken, I was thinking more along the lines of "what did you want me to tell you your springs rates were........... yeah thats what they were"

i dont remember ever once saying that there is only 4 inches of travel.... look guys, its simple, they are what they are. there is no magic inch in there that the spring is ungodly stiff ok. if you think there is, then by all means think what you want.
I give up.

http://www.rx8club.com/showpost.php?p=2156014&postcount=32

http://www.rx8club.com/showpost.php?p=2156035&postcount=33

I'm not trying to give you a hard time, but when something doesn't add up you have to get down to the bottom of it.

I have the Mazdaspeed Springs and struts, and I think they are a great setup. I had them tested and they are definately the stiffest setup available for the 8. And you can believe me, after all.....I'm Tom Brady.

^^^ ha ha ha,.... well there you go. from mr. Brady himself.


Lion, the first MEASURABLE INCH. your trying to find a loop hole in my testing for no reason. I DID skip the first inch, to be honest I even skipped a little more just so I was closer to the actual tension of the spring. and I went ALMOST to the end. when your strut is fully compressed on the car the spring is STILL not fully compressed. so yes there is more the 4 inches I mentioned. there is no magic to this maddens. there is no magic inch in the Mazdaspeed or any other spring that is going to be stiffer then the rest.

send me a spring (because I no longer have any) and I will measure from the moment it touches the perch to the moment the coils are touching each other. I will give inch by inch readouts. but I am telling you, there will be no magic inch that holds any more spring rate then the other inches.

hell I will even video the whole process and post it on you tube. or you can come on over and see for your self. I don’t care how but please for the love of god people either think about your arguments for a second and realize I know what the hell I am talking about, or come see for yourself. :) I'll even let you do it that way you cant say I did it at the wrong time of day. ;)

or again, just trust the numbers that were posted on this forum by god knows who that never even tested them because they heard from a guy that heard from a guy that has a friend that is a dealer at Mazda that once heard that they were 280 pound springs. there is no rhyme or reason for the 280 pound springs, just accept the fact that that number is bogus and move on.)

I might have drank too much last night (and i did... damn eagles were suppose to get blown out quickly), but last i checked there is roughly 750lbs of weight sitting on the front tires. If the front MS springs are ~170 lbs/in they would need a little over 4 inches of compression to hold the static weight... and if they have a usable range of 4" of travel they would be basically in coil bind with the car sitting on the floor

...let me look at that again when i'm more sober...

Someone beat me to it . . . thanks for pointing out the lever factor.

I will say, as much grief as I'm giving speeddemon at the moment, my first cut is to believe his tested rate. The coils of the Mazdaspeed spring is thicker, which increases the rate, but there are also a lot more coils in the setup, which decreases the rate. My instinct tells me the tradeoff between the two might be a wash. Of course I can do a rough rate estimate of the two if someone is willing to give me the approximate coil diameter, wire diameter, and the number of coils per vertical inch.

;)

What are you planning on doing with your car Lion? Are you competing with HPDE events, SOLO 2, drifting...what?

I hope you don't tell me that your just trying to find a good spring for your daily drive....

^^^ yeah no kidding. :-/

What are you planning on doing with your car Lion? Are you competing with HPDE events, SOLO 2, drifting...what?

I hope you don't tell me that your just trying to find a good spring for your daily drive....

I was starting to wonder the same thing...

What are you planning on doing with your car Lion? Are you competing with HPDE events, SOLO 2, drifting...what?

I hope you don't tell me that your just trying to find a good spring for your daily drive....

Let's just say for my purposes I need a setup that is less aggressive than a track setup. Something that is more forgiving of bumps and retains all the travel that the stock setup has to deal with dips and drops while at the same time being stiffer than stock to help improve transition characteristics.

I'm not in a huge hurry to improve my suspension though as that's not the part of the package that needs the most work right now...

Let's just say for my purposes I need a setup that is less aggressive than a track setup. Something that is more forgiving of bumps and retains all the travel that the stock setup has to deal with dips and drops while at the same time being stiffer than stock to help improve transition characteristics.

I'm not in a huge hurry to improve my suspension though as that's not the part of the package that needs the most work right now...

in other words: daily driver with a heavy foot.

in other words: daily driver with a heavy foot.
In other words.....oh, never mind.....+1

Lol

you mean........ oh never mind.... :-/

in other words: daily driver with a heavy foot.

Put words in my mouth if you like, but if I were going for a racetrack setup I have my choice of coilovers. If it was just a daily driver there's no point in improving transition characteristics. How many chicanes are there in the LA concrete jungle?

Put words in my mouth if you like, but if I were going for a racetrack setup I have my choice of coilovers. If it was just a daily driver there's no point in improving transition characteristics. How many chicanes are there in the LA concrete jungle?

I didn't put any words in your mouth, just deciphered your response. Look, there's nothing wrong with improving your suspension and wanting to know eactly what you're buying but don't you think you took this a little too far????
Wow...

Awhile back speeddemon32 tested the Mazdaspeed sport springs and found them to be at a rate that was something like 180/100. http://www.rx8club.com/showpost.php?p=1883212&postcount=100 Of course, the rate that was previously agreed upon here was 280/190 and some people continue to believe that rate. In addition, I e-mailed a vendor and he told me the Mazdaspeed coilover spring rates are 40% stiffer than the sport springs. Since the coilovers are 400/275, 280/190 for the sport springs would make sense. So with so much conflicting information, does anyone actually know what the Mazdaspeed sport springs are?

So let us review. The only information that we do have from a forum member actually testing a product is 180/100...but yet you still want to believe in information that was agreed upon on this forum, in which no one has ever been able to determine the origin, and in which DPE (a forum vendor) even indicated was not accurate, and told to you by another vendor that you called. Maybe what would be prudent at this point, to prove your side of things, would be for you to call that same vendor back, and ask him where he got his information.

In contrast, what we have also told you was the conversation Speeddemon32 had with techs from Mazdaspeed. Why is this information more beleivable (in my eyes)...is that Speeddemon32, like I, were trying to get a spring setup for track applications....so numbers were important to us. We both had reasons, important ones, to find out the truth.

I went more blindly into things than Speeddemon32 did. I beleived, as you still do, that the original forum myth of 280/190 was valid. I bought the springs based on this, as well as other forum members who used their butt dynos and amatuer tracking experience to provide feedback on the springs.

Ultimately, springs, struts, alignment....are preferences to driving style, track, conditions....etc.

Since it sounds that you are not looking for a track application at this point, just get yourself a set of lowering springs and call it a day.


{EDIT}Another thing to consider is the term "sport" spring.

^^^ WOOT WOOT!

this thread reminds me of the whole "well I put this intake on, which sounds better then your intake, so there for I MUST have more power then you. and since It makes more power, it MUST have picked up at least 10 H.P! wow I feel such a difference" thing.


my problem was/is not really the whole concept of the thread, someone had a question and wanted to question somethign about my testing method.... fine. by all means, ask questions. but when I go into such deatail, and provide undisputable proof, and the someone keeps drilling, looking for every last nook and cranny of a shread of a chance that i might be wrong.

its not rocket scince, like Kwescott said, NO ONE ever said for sure mazdaspeed (or any other spring) spring rates were what they were. except me.... not even MAZDASPEED said they were what this forum myth is.

my eibach spring for a custom race car tagged from Eibach at 500 pounds test as a 500 pound spring. backing up their claim. same with the 700 pound spring, same with the stock RX-8 front spring, same with the stock RX-8 rear spring. but no one questions those results. it just boggles my mind when I am only questioned on the Mazdaspeed and Vogland springs because the results didnt come back what you wanted.

sorry but my dyno results came back at 201 h.p. but they were not what I wanted, I wanted 450.. there for the dyno must have been wrong.

thank you Jedi and Kwescott for seeing clearly. I say we start posting more rumors of spring rates just to make people feel better. what do you say? the new Sprint spring rates according to my friends friend is 450/350. I think I even heard Tein say theirs was 550/475. oh, oh... I got it, the new Intrax springs are 280/190 just like Mazdaspeeds.


.

Here's why I started this thread; for my application 280/190 was basically the rate that my first cut analysis told me I needed. Coilovers are a bit stiffer in rate than optimal and lowering springs are pretty pointless to me as what I'm after is not lowering but a stiffer spring;if anything I'd want to keep the stock ride height and suspension travel is VERY important. I e-mailed a couple different vendors, and Online Mazda Parts told me 280/190 sounded similar, DPE said that he didn't have any springs to test, but based on the weight and setup of the springs he had his doubts on the spring being a rate that was close to stock. As evidenced, Team, among others, was still quoting the 280/190 rate. Therefore, I'm sorry if I didn't take speed's word to be gospel, but there were still differing opinions and here was a spring where one quoted rate was exactly what I needed so of course I'm going to get down to the bottom of it. For what it's worth, I quoted speed's misgivings about the Mazdaspeed spring rate on several threads that had people considering them, I wasn't trying to stick my head in the sand and continuing to believe 280/190 regardless, however I was going to figure out exactly what rate that spring is. I haven't bought anything, but I'm doing my due diligence in researching every possible option before making a decision and putting my money down.

and that does make sence. I am all for asking questions. but some of those were getting crazy. (maybe not all yours, there were a few people asking questions)

but when I am told there is more then 4 inches of travel... yeah I know that. do you really want me to tell you that the part of the spring your not using IS ALSO 180 or 100 pounds? its not going to change. besides, I have to go past the first part of the spring jsut to test the rest... trust me, there were no mirical rates down low either. it really was pretty close. hell one of the springs even started to fall of towrds the end as you can see in my results. instead of getting stronger it got weaker. as "progressive" as they are, they are really pretty linear.

even if you wanted to throw a margin of error in there, what do you think it would be? 10%? (which would be high)... so that would mean the 180 pound spring is really 198 on a good day.

again, I guess my biggest problem with everything is whaen I was being questioned as to how I cam up with my numbers on the Mazdaspeed springs and the Vogland springs, when I was not questioned how the other 4 springs came back just as they were supposed to. like I knew how to test those, but not the others... as if they are different.

Make sence?

where are these "as you can see in my results" located :dunno:

and that does make sence. I am all for asking questions. but some of those were getting crazy. (maybe not all yours, there were a few people asking questions)

but when I am told there is more then 4 inches of travel... yeah I know that. do you really want me to tell you that the part of the spring your not using IS ALSO 180 or 100 pounds? its not going to change. besides, I have to go past the first part of the spring jsut to test the rest... trust me, there were no mirical rates down low either. it really was pretty close. hell one of the springs even started to fall of towrds the end as you can see in my results. instead of getting stronger it got weaker. as "progressive" as they are, they are really pretty linear.

even if you wanted to throw a margin of error in there, what do you think it would be? 10%? (which would be high)... so that would mean the 180 pound spring is really 198 on a good day.

again, I guess my biggest problem with everything is whaen I was being questioned as to how I cam up with my numbers on the Mazdaspeed springs and the Vogland springs, when I was not questioned how the other 4 springs came back just as they were supposed to. like I knew how to test those, but not the others... as if they are different.

Make sence?

Very simply, I asked you if there were only 4 inches of travel in the spring and you said yes. Perhaps what you meant was that there were 4 inches of compressed travel or something else, but as it stands I made my calculations and assumed 4-5 inches of spring travel and that did not turn out too well. Of course I'm going to back your assertions with calculations, especially for something that was being disputed; in order to have a good point empirical observations need to be confirmed with theoretical calculations and vice versa or else something is wrong. I make no apologies for my methods.

Blah blah blah just go drive it and see if you like it. I can assure you they're way stiffer than stock and so can many local RX-8 autocrossers of a national caliber. My car has almost no body roll/brake dive and transitions faster compared to B-stock cars with stock springs and the same Konis on thes same settings.

ok, I do have to respond to this......I would have to disagree. I think the MS springs are much the same as stock with reguards to body roll and transitioning. While the MS struts are stiffer, overall, I am very dissapointed with the MS setup when I have driven other cars...namely those in B-stock who have Koni struts (and stock springs) .

I would think that the best solution for Lionzoo would be to get a set of Koni Yellows. This would offer him the transition needs he desires, as well as maintaining the ride height he wants to maintain.

I would think that the best solution for Lionzoo would be to get a set of Koni Yellows. This would offer him the transition needs he desires, as well as maintaining the ride height he wants to maintain.RacingBeat would be the best choice then (rather than keeping stock). 20% spring rate increase with a half-inch travel compromise.

Racing Beat and Koni's...stock and Koni's.....which ever, the main improvement is going to come through on the strut, not the spring.

where are these "as you can see in my results" located :dunno:

... are you seriouse?

Very simply, I asked you if there were only 4 inches of travel in the spring and you said yes. Perhaps what you meant was that there were 4 inches of compressed travel or something else, but as it stands I made my calculations and assumed 4-5 inches of spring travel and that did not turn out too well. Of course I'm going to back your assertions with calculations, especially for something that was being disputed; in order to have a good point empirical observations need to be confirmed with theoretical calculations and vice versa or else something is wrong. I make no apologies for my methods.

ok fine, you win..... :banghead: :banghead: :banghead: :banghead: get the Mazdaspeeds. :lol: :lol: :lol:

Blah blah blah just go drive it and see if you like it. I can assure you they're way stiffer than stock and so can many local RX-8 autocrossers of a national caliber. My car has almost no body roll/brake dive and transitions faster compared to B-stock cars with stock springs and the same Konis on thes same settings.

look more proof Mazdaspeeds are stiffer.... :lol2::rollingla :yelrotflm

ok fine, you win..... :banghead: :banghead: :banghead: :banghead: get the Mazdaspeeds. :lol: :lol: :lol:

Didn't I say I tend to agree with you on your Mazdaspeed rates? I'm just giving the reason for why I gave you such a hard time in asking all those questions.

... are you seriouse?

yes, I saw general rates posted but never saw graphs or rates vs compression distance as implied in your reply :dunno:

Didn't I say I tend to agree with you on your Mazdaspeed rates? I'm just giving the reason for why I gave you such a hard time in asking all those questions.

ok. :)

yes, I saw general rates posted but never saw graphs or rates vs compression distance as implied in your reply :dunno:

ok :)

It's been determined LionZoo just wants to take corners quickly. Maybe he should just get the RS*R Titanium springs. Could we get more info on the alloy composition of each spring to determine elasticity? How about ambient temp?

Maybe we can discuss whose penis has a higher spring rate? This thread is awesome!

I drove an 8 with MS struts and spring yesterday. It looked good and drove great. Roads around the shop were pretty crappy and the car didnt balk at all. I'm seriously considering them now.

It's been determined LionZoo just wants to take corners quickly. Maybe he should just get the RS*R Titanium springs. Could we get more info on the alloy composition of each spring to determine elasticity? How about ambient temp?

Maybe we can discuss whose penis has a higher spring rate? This thread is awesome!

:rollingla :rollingla :rollingla :yelrotflm :yelrotflm :yelrotflm

Not to add to the speculation, debate and skepticism but if people are asking who came up with the 280/190 number... I've got your answer...

http://www.mazda.co.jp/accessories/mazdaspeed/parts/sus02_list.html
http://www.keiyo-parts.co.jp/spring.size.jpg

if you can pull 280/190 out of that link, you're the man. Could I get a Whopper as well :)

With or without cheese?

http://wwwrsphysse.anu.edu.au/~amh110/Technical_pages/coil_spring_rate_conversio.htm
49.0 N/mm = 280 lbf/in
33.8 N/mm ~ 190 lbf/in

without cheese...trying to lose some weight. :)

The Mazdaspeed tech informed me that the MS springs are made by Eibach.

With or without cheese?

http://wwwrsphysse.anu.edu.au/~amh110/Technical_pages/coil_spring_rate_conversio.htm
49.0 N/mm = 280 lbf/in
33.8 N/mm ~ 190 lbf/in

How did you find that link? Good job, so for the first time we have #'s straight from Mazda. Now this will stir up more debate.

Put words in my mouth if you like, but if I were going for a racetrack setup I have my choice of coilovers. If it was just a daily driver there's no point in improving transition characteristics. How many chicanes are there in the LA concrete jungle?Chicanes not many, Chicanos on the other hand, there are millions, and you would need a totally different suspension setup to maneuver those... :dubs:

Aside from that, believing a butt-dyno over solid numbers in lame.

Butt-dyno philosphy is like this;

Black-Lung-Guy: When I feel nervous or stressed, cigarettes make me feel better. Therefore cigarettes are good for me.
Half brain human: But it's been proven that cigarettes cause cancer, doesn't that concern you?
Black-Lung-Guy: My dad smoked 2 packs a day since he was 15yrs old until he died.
Half brain human: How did he die?
Black-Lung-Guy: He got killed in a car accident on his way home from chemotherapy, but the cigarettes didn't kill him.

I typed the part # into Google - it was the second link. Go figure. :)

How did you find that link? Good job, so for the first time we have #'s straight from Mazda. Now this will stir up more debate.

Didn't K/N post some rediculous HP gains on their first version intake for the RX8. Posted information is what I went on as well when I bought the MS suspension setup. I wouldn't have known differently, without the testing done by Speed. Do you recall the hostility and feeling of being taken advantage of, by all those who bought version 1 K/n Typhoon Intakes....

...or those that bought the RX8's when Mazda posted that the HP number was 271........

...point is, can't trust butt dynos....take posted numbers as marketing points to sell a product...tested products by an actual user....I have to give some credibility to.

Disclaimer: I buy Racing Beat products because their advertised gains have been replicated by private users. I bought MS based on butt dynos and posted numbers. Am I happy with both....sure. Would I be just as happy with different products....probably.

Why so ambivelent.....because I'm not a professional race car driver and I continue to learn with each vehicle I own what preferences I have.

I have learned with the RX8, that I will never place an aftermarket clutch or flywheel on a vehicle...and that pulley's seem to be worthless.

If you ask Racing Beat the only intake they know of that makes more HP than theirs is the K&N.

I don't think Mazda ever claimed 271. They claimed 248hp vs the real 238hp.

Regarding the springs - you say potato and I say potato (this doesn't really get conveyed well in text). The spring rate info that Mazda claims is pretty buried and non-existent on any Mazda N America site. They aren't exactly looking to make a killing on these things based on price and lack of info. They must have concluded those numbers somehow. I don't care how, I like mine and we should let those that don't believe Speed's compressor to piss off and believe whatever they want. He's not going to bankrupt Mazda by making everyone look elsewhere. He's also not promoting anyone else's product, just providing a public service. Knowing is half the battle!

http://pic9.picturetrail.com/VOL268/1924163/3716179/94116161.jpg

^^^ well thats just an RX-8 for you.

and yes, You can not trust manafacture numbers. I belive K&N claimed 10 h.p. realistically its more like 2. ;) this comming from a guy that LOVES his K&N.... but untill someone does REAL test, both the numbers 10 and 2 in my book are worthless.

If you ask Racing Beat the only intake they know of that makes more HP than theirs is the K&N.

I don't think Mazda ever claimed 271. They claimed 248hp vs the real 238hp.

Regarding the springs - you say potato and I say potato (this doesn't really get conveyed well in text - let's call the whole thing off).

Mazda changed their minds on what the RX-8 could produce more then once. I have a magazine artical (well several accually) that say Mazdas RX-8 will be 255 h.p. then after the big hype of it not producing that they lowered their claim to 238. not trying to diss mazda here, but more proof you cant trust their numbers. :tear:

Didn't K/N post some rediculous HP gains on their first version intake for the RX8. Posted information is what I went on as well when I bought the MS suspension setup. I wouldn't have known differently, without the testing done by Speed. Do you recall the hostility and feeling of being taken advantage of, by all those who bought version 1 K/n Typhoon Intakes....

...or those that bought the RX8's when Mazda posted that the HP number was 271........

...point is, can't trust butt dynos....take posted numbers as marketing points to sell a product...tested products by an actual user....I have to give some credibility to.

Disclaimer: I buy Racing Beat products because their advertised gains have been replicated by private users. I bought MS based on butt dynos and posted numbers. Am I happy with both....sure. Would I be just as happy with different products....probably.

Why so ambivelent.....because I'm not a professional race car driver and I continue to learn with each vehicle I own what preferences I have.

I have learned with the RX8, that I will never place an aftermarket clutch or flywheel on a vehicle...and that pulley's seem to be worthless.

I bought the MS setup because it was the only setup out here that was matched up to each other and to the car, not because of some numbers. You are right about #'s being marketing ploys. Testing by more then one user is what I would count as credible, though his testing does raise questions. I would be interested in seeing two other users testing the springs. To many variables to take one test as the right #, bad spring tester, or bad set of springs. If three tests come in around the same # then I'll be convinced. As far as clutch, flywheel, and pulleys, your right that the performance gains may not be all that worth it but for some people the process of working on their car makes it worth it. The pulley I added probably freed up 1HP, do I feel it? Well No, but it was fun installing it and stripping 2 of the bolts:(

Mazda changed their minds on what the RX-8 could produce more then once. I have a magazine artical (well several accually) that say Mazdas RX-8 will be 255 h.p.

The magazine wrote 255, not Mazda. Once released they always claimed 247... until they claimed 238... and then 232...

The magazine wrote 255, not Mazda. Once released they always claimed 247... until they claimed 238... and then 232...

232 was due to revised SAE testing procedures, not Mazda's fault on that one.

I know.

hp, parts, and dynos......what a big frustration. We had a local dyno day down here in So cal..with about 20 RX8's with varying level of modifications...even had a couple of ATs showing up. I had one of more heavily modified 8's and I had one of the lowest dyno results. It was very dissapointing.

We don't want to get off track though, as we are talking about springs. I am pleased with the MS setup as it fits my needs, and works well with my bodykit and wheels. It is perfect for me, I wouldn't change it for anything (as a daily driver...which mine is....Im at 77k miles now)....but as for autocross, which I also do....I think there are better setups.

wow.. 5 pages of nonsense.......

i personally know speeddemon and his entire family.... his father was a professional racecar driver for damn near all of speeddemons life... speeddemon was part of his father pit crew for years. take what i say with a grain fo salt, but if he says the spring rates are what they are.. then thats what they are!

and after reading all of this, ive noticed that the ONLY one who has ACTUALLY done any testing is speeddemon... but numerous people are chiming in with their "butt dyno" results like they are concrete evidence! obviously those poeple are just making fools of themselves....

lionzoo.... im much like you in the fact that its really hard to believe anything thats put on the internet.. and i tend to go as far as you in finding out exactly what i need to know... but in this situation, and with me personally knowing speeddemon and his testing methods, i'd take his results as the answer you were looking for! becuase if you notice, nobody else has actually tested them on a spring rate tester, they only have their "butt dyno" to chime in with:)



kwescott.... as for your comment about never installing a aftermarket flywheel or clutch on any car again.... the rx8 seems to be one of the worst mod friendly vehicles in the world... but there are MANY cars that these mods really do make a big difference... take my evo for example.... the factory clutch is very spongy and weak... just about any aftermarket clutch out is better than mitsubishis... and lightened flywheels are great for some cars, but not all.... same goes for underdrive pullies... some cars show major power increases when pullies are installed.. the evo in that case isnt one of them.. they are a waste of money much like they are on the rx8... but i just had to comment because your taking the headaches youve acuired from your rx8 and trasferring them to all cars in general

speeddemon.... take what was said in this thread and shrub it off.. you know your right, and your the only one who actually took the time to do these tests...

ghost.... your a very smart person, which is why its suprising that you are taking your buttdyno results and trusting them more that a tried and true method of testing spring rates.... casey knows how to test progressive spring rates, so you should trust the results given, even if they dont truly agree with what you thought you felt when driving...:) but in any case, you got smart and got jic flt-a2's just like me:) we're so cool:):)

The magazine wrote 255, not Mazda. Once released they always claimed 247... until they claimed 238... and then 232...

that does not help your case much. ;)

I bought the MS setup because it was the only setup out here that was matched up to each other and to the car, not because of some numbers. You are right about #'s being marketing ploys. Testing by more then one user is what I would count as credible, though his testing does raise questions. I would be interested in seeing two other users testing the springs. To many variables to take one test as the right #, bad spring tester, or bad set of springs. If three tests come in around the same # then I'll be convinced. As far as clutch, flywheel, and pulleys, your right that the performance gains may not be all that worth it but for some people the process of working on their car makes it worth it. The pulley I added probably freed up 1HP, do I feel it? Well No, but it was fun installing it and stripping 2 of the bolts:(

I agree, I would LOVE for a couple more people to test a set. I DO NOT agree with your bad spring tester idea though as I tested the 500 and 700 pound springs and they came back as they should. (and the stockers). but maybe I did have a bum set of MS springs. I cant deny that. my ONLY form of backup on that is when I called Mazda and they said they are not advertised as stiffer. but again, maybe they were a bum set. by all means someone please test a set of MS springs to see what the rates are. it really is the only way to confirm my results. (just make sure you have a couple controll test to verify the test is working as it should..... you know.... kinda like I DID! ) :)

speeddemon.... take what was said in this thread and shrub it off.. you know your right, and your the only one who actually took the time to do these tests...


THATS WHAT I KEEP SAYING!!! :)
I REALLY REALLY want someone else to test springs to... I just dont know anyone that has the ability.
but thanks!

So here is the deal ;


If everyone here pitches in a few bucks, We can go rent 3 spring compressors/testers. We use at least 2 "control" springs. And then the mazdaspeed springs. ( and any others we want to try out.) And whoever is right gets to say "neener neener neener" to the others.


Now we already KNOW how the tests are going to turn out. But if we really need to do it, I will organize the $$ and the rentals. I will also find a non biased person to do the tests.

***raises hand***

It's funny this topic was discussed in the same way over at vwvortex (used to have a GTI before it was ripped off.) Anyway one guy decided to test every spring he could get his hands on and the results shocked everyone there. As for me that is why I am very sceptical on changing springs. Unless the manufacture can provide you with exact rates and not one of these % stiffer #'s I would not trust it. It is amazing that we have someone here that has a tester and can give us actual rates.

I have to agree that the increase in stiffness is mostly due to the improved struts or to the fact that the car when lowered runs out of travel and rides on the bumpstops which are as stiff as hell (not sure if this applies to the RX8). Maybe someone can let me know how much suspension travel the 8 has at stock ride height before it gets down to the bumpstops.

I was running stock springs w/koni sport yellows on my GTI and the ride was much stiffer then stock even at full soft.

There is also another issue to consider when you change springs. If your new springs don't keep the same ratio front to back your car's handling will change, more understeer if the front spring rate is higher in relation to the rear and more oversteer if the rear spring rate is higher in relation to the front. This also applies to sway bars. I feel many of these manufactures tend to increase the front spring rate more then the rears to make the car understeer more in a way to make the cars more forgiving in the hands of everyday drivers.

Keep up the good work speeddemon32

ok :)

ok what??? :squint: :squint: :squint:

Did you post the info as you claimed or not? :dunno:

So here is the deal ;


If everyone here pitches in a few bucks, We can go rent 3 spring compressors/testers. We use at least 2 "control" springs. And then the mazdaspeed springs. ( and any others we want to try out.) And whoever is right gets to say "neener neener neener" to the others.


Now we already KNOW how the tests are going to turn out. But if we really need to do it, I will organize the $$ and the rentals. I will also find a non biased person to do the tests.

sounds like a good idea! though I doubt anyone will step up. most people are willing to piss and moan, but not willing to acctually do something about it. anywhoo, if you need my help with anything, just let me know. I obviously will not be the person doing the test, nore will it be my spring rate tester (just incase my tester is biased to anything other then RX-8 springs, except for the stock ones of course, because it said they were what they were supposed to be).

for your/their test I would assume you would want the following.

Spring rate tester
2 front stock springs
2 rear stock springs
a KNOWN spring and its rate (like I had the 500 pounder)
maybe a second one. (like I had the 700 pounder) (the above 6 springs will establish that the spring rate tester is functioning, and the person doing the test knows what he/she is doing)
a set Mazdaspeed springs, maybe 2 or 3 since those seem to be the most in question.
any other springs in question
and a witness...... or ten.
maybe a Notary or two.


ok ok, the end of that was a little smart assish, but seriously, that is what you would need to validate any results. (not the notary). also make sure the person notes EVERY SINGLE INCH not just mentally, but on the forum or else they will hear about it. ( I guess this was my mistake? )

again, good idea, and good luck. I hope to hear results!

ghost.... your a very smart person, which is why its suprising that you are taking your buttdyno results and trusting them more that a tried and true method of testing spring rates.... casey knows how to test progressive spring rates, so you should trust the results given, even if they dont truly agree with what you thought you felt when driving...:) but in any case, you got smart and got jic flt-a2's just like me:) we're so cool:):)

hahaha. you give me more credit then i deserve.

but in any case, its a dyno. i cant really argue with that especially given speeds background.

;)

thanks Ghost... and you are a smart guy, you know what your talking about. just dont trust your butt dyno all the time. I know I cant trust mine. mine seems to be broken. (I think we have talked about this before. :) )

its not really the backround I am trying to have as my support here. rather the numbers that speak for them selves. I stand by my self and I know the test was done right.... its not rocket science.

the only argument that I am seeing (now) is that I did not type more then 3 inches of travel.... I think "these people" have agreed (now) that I know how to test springs, and that the rates are right. their complaint or argument is that I did not type the rest of the inches. I dont know why this got blown up like it did. I am telling everyone that I saw the entire range and it never did anything special. next time I will be sure to type up every single inch. then hopefully they cant complain. :)

anywhoo, see you next week? :)

speeddemon, i would like to contribute to some tried and tested research into this spring. i currently bought a set of RB springs. installed the fronts and not even noticed a hair in drop. the rears are not installed yet. i was wondering if its not too much trouble to have the rears tested for its spring rate.

i also have a formula to follow under measurements to determine a set of spring rates for a given spring by measuring its dimensions. i bought a digital caliper and would like to do some testing using simple formula's to get a given number. i have a very handy book by fred puhn called "how to make ur car handle" and would like to see their formula's if they work or not.

is there something we can work out? i know a stock spring to test is useless. but in RB's catalog it claims 174/122 and not whatever someone else posted that has not been revised with something like 187/136???

i like to find REAL proof and help give REAL proof that manufacturers numbers are indeed marketing strategy. but i'd also like to use simple formula's that don't need any machine's to also help determine spring rates and exploit the use of that as well, as i've noticed RB's set has 8 coils to the stock 7 coils on its springs.
this way, if its really proven on the machine( ur compressor tester) and proven with the recommended formula, we can all pretty much be educated buyers in the science of vehicle dynamics rather than just falling into advertising BS.

i feel u on this project. and so far...its a given. to test a spring is to compress 1 inch and find the lbs. and u end up with the given #. wouldn't it be nice to also verify the accuracy of a formula with the help of a cheap measuring tool so we can simply walk into a speed shop and know exactly what springs with what # of coils with what diameter wire and etc. would equate to what spring rate?

i just want to help. let me know if u wanna help make this worthwhile.
and to say the truth... i would only like to spend any $$$ on performance. and i'd like to know if i'm getting ripped off. so i'm very eager to accomodate in this research.

magic. absolutly!
come on over, I will test it for you. (hell I'll even let you do it if you want) and we will be sure to document every inch. :)
contact me over PM if your intrested, I'll give you directions. :)

Ohh... sounds good!

TrochoidMagic, what is your formula for calculating spring rate? I have a formula that does the same thing and I'd like to compare yours to mine.

I'd like to compare yours to mine.

eeeeewwwww. :) he he he. :)

Ohh... sounds good!

TrochoidMagic, what is your formula for calculating spring rate? I have a formula that does the same thing and I'd like to compare yours to mine.

W(4th pwr) G
_____________
K =
8ND(3rd pwr)

K=stiffness of spring in lbs. per inch
W=diameter of the spring wire (in inches)
G= 12,000,000 for steel springs
N=number of active coils (# of free coils+1/2)
D=diameter of the coils (measured to the centers of wire, in inches)
note: an easy way to find coil diameter D is to measure the O.D. of the coil minus wire diameter.

this info is gathered from "how to make ur car handle" by fred puhn.
this book seems very informative and very knowledgeable, however, i use it for an "easy" way to find things. it is not a mechanics training textbook, so the info may or may not be very accurate to modern standards if its off. there are specific formulas i've learned in suspension dynamics and etc. but the textbook formula hardly stays with me as its only practiced occasionally to see if the students can comprehend the formula and its function and to prepare for ASE testings and such.

i'm only stating the above info to inform everyone "no way in hell am i goin back to my parents house to dig up a textbook and research long chapters for one specific application". this should be reasonable enough to start as a foundation formula to test on.

^^typo. separate the K so that its K= blah blah blah over blah...

your "easy" way, seems a lot harder then putting it in a spring tester and testing it. :) also does not factor in quality of the steel.

none the less, its very coo to have that formula. I am sure it gives a close ball park figure. :) good find!

^^demon, i was like eeeeccckkk when i saw that it wants u to factor in the grade of steel strength. and according to RB in its catalog, it uses special "selected" steeel alloys. so if thats only for lighter springs... its like 4.6 lbs in front and 4lbs rear. but what about the strength of the alloys? so yea, that can have a direct factor in finding accurate #'s for that given formula.

like i said... this is just a "handy" book. its really a bible to learn the bases of such and gives quick references formula's. but we all learn that in the REAL world, not all are created equal.

demon, i PM'd u. let me know whats the haps man. i will get back on this thread when i'm back from work. but either way... if u want to help, it'll be cool. i figured someone should be doing the job of policing the aftermarket companies. and if they are lying...RB's goin down! i'm goin back to mazdatrix and returnin my shit!

PM replied. :)

trochoid....the rb springs in front are unusual to say the least. At least in my experience, in the two RB spring installs I've done, the spring is very narrow at the bottom (where it sits in the perch)....and in both cases, the spring (even when installed) did not touch the seat properly.

Upon installing the strut/spring onto the car, it actually raised the vehicle. Following some additional installation instructions....the car did lower to the advertised drop.

The additional instructions have you loosen two of the bolts and allow the vehicle to "settle"...then tighten the bolts.

As far as spring rate on the RB spring....I'm sure if you paid for shipping, Speed would test the spring for you and send it back.

W(4th pwr) G
_____________
K =
8ND(3rd pwr)

K=stiffness of spring in lbs. per inch
W=diameter of the spring wire (in inches)
G= 12,000,000 for steel springs
N=number of active coils (# of free coils+1/2)
D=diameter of the coils (measured to the centers of wire, in inches)
note: an easy way to find coil diameter D is to measure the O.D. of the coil minus wire diameter.

this info is gathered from "how to make ur car handle" by fred puhn.
this book seems very informative and very knowledgeable, however, i use it for an "easy" way to find things. it is not a mechanics training textbook, so the info may or may not be very accurate to modern standards if its off. there are specific formulas i've learned in suspension dynamics and etc. but the textbook formula hardly stays with me as its only practiced occasionally to see if the students can comprehend the formula and its function and to prepare for ASE testings and such.

i'm only stating the above info to inform everyone "no way in hell am i goin back to my parents house to dig up a textbook and research long chapters for one specific application". this should be reasonable enough to start as a foundation formula to test on.

I'm not sure where that 12,000,000 comes from. It should be modulus of elasticity, but if that were the case the number for steel is typically in the 30,000,000 psi range...

I wish this thread would just die...

Unsubscribe aka thread suicide

it's like a bad car accident. I don't want to look, I wish it wasn't even there, but I can't help myself...

^^haha, poor guy. i remembered at first when i kept getting e-mails of the subscribed threads...annoying.

KWESCOTT: yes, the RB springs are actually funny like that. and thats why i'm curious to find out. and my fronts fitted perfectly and had to be compressed to fit... are you sure you put the right ones on? the 14026 are for the front, 14027 are for the rears.

and yes...at first i did get upset and remove and recheck to make sure there wasn't something wrong with the strut top during install. but i just preloaded the car when i re-installed, loosen the a-arm and jack up the suspension when tightening...also had the car's rear end sit up on ramps.

needless to say, the car FINALLY seem to start settling in after a long 2 weeks...barely getting 2 3/4 finger gap....wow.....

oh kwes, i live here in so-cal. so its just a matter of convenience to meet up with demon.

and could it be that these springs have been revised? dunno... but when was ur mod done? in 04? maybe there are 2 version??? again, mine sits in the perch just peachie and a lil too stiff. ride seem actually softer...dunno why, but it does. the rears are still stock, and my friend also verified that the rears catch stiffer than the front... weird.

Anyone seen these in action?

http://www.horsepowerfreaks.com/price/Mazda/RX8/Megan_Racing/Suspension/Coilovers

oh kwes, i live here in so-cal. so its just a matter of convenience to meet up with demon.

and could it be that these springs have been revised? dunno... but when was ur mod done? in 04? maybe there are 2 version??? again, mine sits in the perch just peachie and a lil too stiff. ride seem actually softer...dunno why, but it does. the rears are still stock, and my friend also verified that the rears catch stiffer than the front... weird.

My vehicle has the MS suspension. I've done an RB install in 05 and 07....I don't know whether there have been any changes between that time.

check your pm's.