cortc

Great info and instructions , hmm m another worthwhile expense .

cheers
michael

cortc,

Where in Miami did you do it? I'm thinking of this mod and would want to it with someone with expericnce.

Thanks.

Close up of part number...
 

Here is a close-up of the part number... The car is very smooth, more so than when stock...:)

RX8on19s: I will PM you, are you going to the meet this weekend?

Here is the info...

https://www.rx8club.com/showthread.p...threadid=27481

I'm sorry it wasn't the automatic counterweight. It was the automatic counterweight.

I mean you could have said, "You listed the partnumbers for the front counterweight, but you are right it is the automatic counterweight regardless."

That would have taken some class.

I couldn't read the last four digits only the first 4.

-Mr. Wigggles

Re: Close up of part number...
 

Cool, thanks for the information. I will pass this on the Mazda speed. When I was speaking with them this morning, they didn't have any flywheel kits to check because they are currently backordered (at least at the warehouse). Just to clarify, you got this with the Mazdaspeed flywheel correct? I've kind of lost track, because of jumping around different threads, forums, and actually doing real work.

As far as smoothness goes, it doesn't suprise me. It's not the actual "feel" that I am worried about. It's really difficult to detect an incorrect balance in the engine. Thanks again.

I didn't know I had to have class to answer. Darn, I should have worn my suit.

Please don't take my coments that seriously. I am pretty light-hearted. I quess it's hard to hear my tone of voice in print. I didn't mean to offend you in any way. Please don't egg my car.

Hold on. If the front counterweight is the AT one, but the stock MT with this front counterweight and built-in counterweight is perfectly fine...then why is it an issue if you lighten the flywheel and just match up a counterweight that goes with the AT counterweight? Confused?

If there a problem with the stock setup? Does Mazda need to recall the cars and make a change at the factory in the front counterweight? If not, then why is this an issue with aftermarket counterweights? Shouldn't matching up to the AT counterweight suffice as it did for stock?

Hello, I'm new here so I thought I'd introduce myself a little bit first. I'm a professional mechanic that specializes in high performance. I don't own an 8, yet, but am considering it as a future option. I do own two 1st gen 7's both of which I've owned less than two years. I'm big time into Thunderbird SC's, I have three, which were the '89-'95 models with the Eaton supercharged 3.8 V6. I built one into the 12's at 3800 lbs so I've done a thing or two with late model performance cars. I've built many hot cars in my time and will probably always do so. I'm not here to play know-it-all on this board but I am very knowledgeable on the subject and as I've poked around here I've seen several posts where I can offer some advice. If the majority appreciates it great, but if I start getting flamed because I don't own an 8 or some such junk I'll just take off without any ado. I'll be the first to admit that I'm a Rotary novice, I actually got into them just to learn more about the engines but fell in love with the thing. Me loving a Japanese car, go figure. LOL


Lightweight flywheels work just as well in other cars also, it's just that most people don't realize it and never try it. That and many will always tell you that it'll kill the drivability or you'll lose torque and scare others out of trying them. I've had a 15 lb McLeod flywheel in one of my Thunderbird SC's for years now and it remains one of my faivorite mods to date though it has enough mods to run into the high twelves at best.

Reducing crankshaft weight works extremely well on any performance engine. This is the most effective place to reduce wieght on the whole car as not only is it rotating weight, it is also weight that must be accelerated more than once in a timed acceleration distance. Think about it, driveshaft, wheels, brakes, bodywork, etc. only acheive maximum speed once, at the final point of measure. Whereas the crankshaft and engine driven accessorys have to be accelerated from point a to point b in EACH gear required to reach the finish line.

In my SC I pulled 20 lbs off the crank by pitching the stock truck style factory flywheel and installing the aluminum part. That's 20 lbs less weight for the engine to accelerate up to 6000 RPM 4 times in the quarter, compaired to say 4 lbs I saved using an aluminum driveshaft that only goes from zero to 6100 RPM once in the same distance. With the 9000 RPM Rotary engine the difference is even greater due to the larger rev range it uses.

Vernon

Who's on first, what's on second? Yes it get's confusing, especially when the conversation gets bounced around so much between people.

It's really not that complicated. Let's review: There is counterbalance on both the front and the back of the engine and they are 180 degrees apart (opposite eachother) from shaft center. The rotating parts between the counterbalancers are basically the same. Any change in the front counterweight has to be matched with a change at the back (whether it's a counterweight or stock flywheel). We found that the balance of the front counterweights from AT and MT RX8s are different and this difference is also present at the rear between the AT rear counterweight and the MT flywheel. When you remove the stock flywheel (with it's built -in counterweight, and replace it with an AT rear counterweight the balance is no longer correct.

First: Yes this counter weight came together with the flywheel; in the same box...

Second: These are the exact same parts as are installed on the 300 production Mazdaspeed RX8s in Japan...

Third: The engine is perfectly balanced with these parts installed; this is a well engineered and correct setup for the RX8 MT car...

1. Thanks for the info about the Mazda setup. I am letting them know about the part numbers since they don't have parts to verify at this time.
2. They may have 300 cars that aren't balanced right but working fine, or they may have used the AT front counterweight as well as the rear one to make the balance perfect. Frankly I don't care about what's done in Japan.
3. "The engine is perfectly balanced"?? How can make this claim without taking your assembly apart and sending it off to get balanced? It may FEEL "perfectly smooth", but that's different.

I'll have more information next week when our tooling is done for our dynamic balancer. It will tell us how much descrepancy there is between the AT and MT balance. I am too lazy to do the math with our current bobweight system and it wouldn't be as accurate.

My MS Flywheel installation is on hold until this is resolved in my mind.

ACTman- I will be keeping my warranty intact, hence my rationale for the MS flywheel. Did MS give you any indication what their response would be, what action would be taken, and in what time period?

ACTMan: You have no idea what you are talking about, once again I know for a fact that this is a proper and balanced setup... I myself verified with Mazdaspeed in Japan... Please stop spreading/posting false rumors/statements in an effort to push your own products...

A MT Renesis powered RX8 is perfectly balanced with this setup!

This is my last response...

rxeightr, wait if you feel that is best. I, myself, would just do the MS Flywheel and not worry about it. I believe that ACTman may have a real issue. It's not 100% settled and concluded yet, AND even if he does have an issue, that doesn't mean it carries over to the MS flywheel as well (as Mazda put it together, I'd hope that they'd get it right!).

Worst case scenario... ACTman is right and there is also the problem in the MS flywheel... well it's an official Mazda part, installed at a Mazda dealership. You're covered under warranty. There may be some inconvenience of your car in the shop, but otherwise... it's Mazda's problem to fix in this situation.

No, it's too soon for that. I am working with the US side of Mazdaspeed. I am sure they will have to go back to the Japan operation to make any authorized changes which will take some time. It doesn't sound like anybody has had significant problems with the incorrect balance. The only probable consequence will be increased main bearing wear which will happen over time, and maybe increased vibration (but doubtful from what others report).

Dirk, I think you are offering valuable information to this thread. However, you cannot use the forum to promote your own products unless you first become a paying site vendor. Please contact BOOSTD 7 (Ryan Scott) at advertising@rxtuner.com to arrange this. I have gone back into your previous post and edited out the information promoting your products. Please refrain from posting such info until arrangements are made. Thanks.

Oops, the cops are coming to get me now!
Sorry, I totally understand. I didn't realize this would get so out of hand. I was also meaning to say sorry to the author for polluting the original thread.

off topic regardin the warranty does everything have to be installed through mazda to retain the warranty? b/c that would seriously suck since they are charging 500 for the installation when I found someone that was going to do it for less. darn

Yes, it has to be installed by an authorized Mazda dealership...

The cheapest i can find this flywheel for is $579.00 USD. How much did everyone else pay? How much in labor if you didn't perform the job yourself you think?

Thats not a bad price, it should run about 250.00 for installation...

I emailed Ryan last Friday but no reply yet.

Instead of further polluting this thread and having our info considered suspect, for those sincerely interested in our balancing results drop me an email and I will share what we have learned. Most importantly, I learned Friday from a top rotary race engine builder (name withheld) that even a severe balance error should not harm the engine. So don't over-react (as I could probably be accused of). Have a nice day!

hey cortc... 275 ??? thats actually not a lot maybe the labor rate is different. but the nearest dealarship around here is chargin 500 for install. whats your opinion on that ?

They are gouging, it is disturbing what some dealerships are doing to there customers... It's a 3 hour job tops, so if the rate is 75 your looking at 225-250; anything more than that is padding...

My dealer quoted my $90 an hour, and 6 hours. I told him exactly what you said, and he said he was just padding it "Just in case."

They've never done it before (Stockton Mazda.) Anyone have an experience service department in NorCal, or even in the Bay Area? It would be worth the drive to me to get the piece of mind an experienced tech would give me.

cortc, do you think you could please let me have the correct Mazda part number for the Mazdaspeed lightened flywheel + counterweight so that I can run it past my local dealer here in the U.K. to see if he can get hold of it.
Thanks.

Thanks Rob.

It's a shame I didn't know about this earlier. The costs are very reasonable...

Prehaps - there will be shipping and quite possibly import duty on top of that.

Was looking into it as I need some clutch work doing anyhow. But I'm not bothering for now.

You can get it here in the states for about 525.00, call Rosenthal on the vendor’s forum they usually stock them...

I will look up the part numbers and post, in the meantime I have posted them in the past; try a search...

Would there be any labor savings doing the flywheel change when they are doing the recall for the MT heat sheild?

My heat sheild was backordered, and perhaps a few hundred bucks could be saved doing it at the same time.

Spazm. My dealer quoted me 80 x 5. They said that was padding it.

Replacing a M/T heat shield doesn't shorten Flywheel install labor times enough to give you much of a discount, surely not $200 bucks worth. It would surprise me if it mattered at all. At most the only things shared would be putting the car on the lift and dropping the exhaust. Now if you can manage to grenade your clutch under warranty....LOL.

Vernon

My clutch went out early last week with only 2600 miles. After discussions with Mazda they are covering it under warranty and installing a lightweight flywheel (supplied by me) for no extra charge.

The dealers are examining broken clutches closely for abuse--therefore be careful.

My car went in for the Mazdaspeed flywheel to be installed at my local dealer 2 days ago after I managed to procure the parts from Japan a couple of weeks ago. We agreed I would pay hourly upto a maximum of 5hrs labour. I still don't have my car back :(. Apparently my main dealer doesn't have the correct tools to do the job (but they started it anyway). They are short a 54mm socket. And they are having trouble getting one!! And 2 weeks notice obviously wasn't enough time to get this in :rolleyes:. Idiots. Anyway; a word of warning to all. Please make sure your dealer has one of these before they take your gearbox off!! :) Still, I'm looking forward to it being completed :D (but not the cost of the labour :(). Living in the U.K. can be a pain sometimes...

i love it now how do i convince my dealer to install it

hey toeknbrit you've recieved the flywheel pretty quick, I've ordered mine for like two months now and still haven't arrived :(. Where did you ordered it from?

Is it that tough of an install to do yourself? Doesn't it just involve taking off a few bolts and sliding the transmission back? Or is it more complicated than that?

IZoom-ZoomI, I ordered my Mazdaspeed flywheel from www.japanparts.com . It took less than a week to get to my door (but I am in the U.K.).

I have actually got my car back now. And I'm a little sorry to say that I hardly notice the difference at-all. The pictures of the flywheel are the same as that of CortC's. And according to the dealer the weight differences are minimal. I don't know if there is a different part fitted On U.S., and European models, But??...

Let's just hope that it's a case of restrictive exhaust not allowing the engine to rev up to speed as quickly as anticipated. I have a C.Z. Mid-P-4 on order, and I would like to think this will sort things out. Still; I can't stop myself thinking that I've just wasted a lot of money...

And GooOnYou, I think the install is a bit of a pig. Respect to you if you want to try D.I.Y., but please make sure you have a 54mm socket handy :D...

hmm thats strange usually lighter flywheels you do notice a difference with the driveability. It doesn't really make much sense since the mazdaspeed flywheel is quite a bit lighter than stock, unless u.k rx8's are different from american spec versions which i highly doubt ... from what I've read from a lot of respected members of this forum that the flywheel had a noticeable affect on their cars you're the first one that said there isn't any difference that is strange, any comments guys?

What can I say?? The Mazadaspeed flywheel was my 1st mod.
I'm just telling it the way that I feel it. I'm kinda bummed too :( ... I'm holding onto the hope that the engine can only run as fast as it can lose the exhaust gasses, and the standard midpipe/cat is restricting that. I'm probably wrong, but at the moment I'm trying to justify the cost...

Nah, you shouldn't have to get rid of the cat to notice flywheel gains.

Tokenbrit, was it made of Aluminum or steel? It's hard to believe that there was little wieght difference between an aluminum piece and the factory steel one. Speaking from personal experience you should have noticed a big difference if you got the right flywheel.

Vernon

I haven't weighed each flywheel back-to-back, so I don't know the exact weight difference. The Mazdaspeed flywheel did look exactly the same as CortC's tho. And I am guessing that there is only one Mazdaspeed flywheel available. The one that come off is cast (and ugly), and the Mazdaspeed one is 2-piece, and pressure forged (Chromoly for the flywheel I think - Steel for the counter weight).
I gave the garage my digital camera for some pics when they got the car. It shows them back-back. I will also take a pic of the Japanese Mazdaspeed info I got when the part arrived (maybe one of our Japan members can confirm that my Mazdaspeed part is the correct one :rolleyes: ). I will try and post these later (when I retrieve my download cables from a friend).

BTW, I haven't done much driving since the mod yet; but the difference I feel at the moment is NOT significant :confused: .

Right; I've now had a bit of a drive. Still not a significant difference I can feel while driving. There seems to be a pretty significant difference when the car is revved under no load tho (i.e. - in neutral). It revs much more nicer :) .
The stock flywheel also feels much heavier than the Mazdaspeed one did.
The part info I have been given by the shipper (www.japanparts.com) for the Mazdaspeed lightened flywheel set is Part No. - 091-013-011, Part Description - Mazdaspeed lightened flywheel set.

Surely there is only 1 Mazdaspeed lightened flywheel set in existance?? :confused:

Can somebody please put my mind at rest, and confirm I have just had the correct part fitted. :p

Here are some install pics. Please note both flywheels besides each other.

Honestly I don't know if there are two types of Mazdaspeed flywheels. In any case the one you put in is a big improvement over the stocker. The differences in reduced crank weight are most noticable in the lower gears where the engine revs up faster. In your end gears it would take a stop-watch and a measured distance to tell the difference. Reducing flywheel weight doesn't cause the engine to produce any more power, it only uses less of what the engine has always been makeing. The newly released power accellerates the car faster. But it's all a power constant with a wieght divided by time thing. Same power with less weight to move equals faster speed. The faster you try to move that wieght, as in the lower gears, the bigger the difference in wieght reduction.

If your Mazdaspeed flywheel is a lightened steel unit as opposed to a cast iron stocker, then you have a very strong flywheel that falls in the moderate wieght reduction range. This is good for a street car as it's bulletproof and easyer to drive in stop and go traffic. If you had used an aluminum part you would have maximum accelleration benefit with slightly more clutch slippage or throttle application to get rolling.

If there is only one Mazdaspeed flywheel and it's a lightwieght steel type then that makes your choice on flywheel replacement boil down to this, do you need to retain the Mazda warranty. Yes = use it. No = go for aluminum and get the most impact on your time and money investment. With a "super" light wieght wheel there would be no questions on its effectiveness. With the steel it's there, just not as dramatic. It all adds up though, don't turn sour on mods. No one mod made the fastest car.

Vernon

Thanks Vernon.

Retaining the factory warranty on the engine is kinda important to me right now. This is why I went with Mazdaspeed, and got it installed at a main dealer. And I didn't want the car 'too wild' as it is a daily drive. I WAS hoping for more 'bang' for my buck tho... :cool:

Still, my C.Z. Mid-P-4 (Random high flow cat and resonator) is on order. Maybe I'll get more joy when this arrives... Then it's FI. :D and Mazdaspeed sway bars. :D (not necessarily in that order :) )

Could somebody please confirm that I have the correct Mazdaspeed part tho. I would like to know for sure. :rolleyes:

The parts are correct, not only is it lighter but the mass is concentrated in the center... The MS unit weighs in at about 10.5 lbs most aluminum ones weigh in at about 9.5 lbs so the difference is not much...