alz0rz

iTrader: (41)

weird.. Espelirs didn't come across as crappy quality...

shaunv74

Other people have them with the stock shocks and I think they are fine with high pressure shocks like the Tokico D specs. They just shouldn't be used with the Konis or other low pressure shocks. I had them with the stock shocks for almost a year and they were fine. As soon as I used them with the Konis I had problems.

kristopher_d

So, do you suspect it was the spring binding/un-binding, or was the excess sag causing interferance for other suspension components?

shaunv74

You know it's tough to say. I am thinking it was interference caused by the low ride height and reduced suspension travel because I could reproduce is while sitting still and turning the wheel while on an incline and low speeds in a parking lot. The coils aren't really being stressed when turning the wheel and sitting still.

At the same time I think the clunking when braking and hard cornering was the coil binding. So I'm going to call it two different problems remedied by removing one incompatible component.

LionZoo

Aren't D-Specs also twintubes like Konis? Do they run at a higher pressure than the Konis?

shaunv74

I think they are monotube high pressure similar to the OEM which are also made by Tokico.

shaunv74

Did I mention the rear springs suck to swap out...

dannobre

iTrader: (3)

Don't like taking your trunk apart

They are easy if you do it right...just don't follow the FSM......there is a much easier way

TeamRX8

iTrader: (25)

swapping the springs is easy, getting the assembly in/out of the car is what sucks

DOMINION

^Good trick is jack the car up enough so you have enough room to clear things.

Astral

I thought rear springs were not that bad at all. Maybe a little worse than the fronts. The parts that are harder are putting the springs back in (lining it up with the top seat and having it seat in there), as well as lining up the camber cam and putting it back together.

shaunv74

The car is up enough. It's the springs getting caught between the flange around the swaybar endlink and the axle. I got it out last night so hopefully it will go back in easier. I unbolted the lower control arm (marked the cams) but it doesn't seem to want to rotate down so I didn't try to force it too much.

Hopefully things will go smoother getting it back in tonight...

shaunv74

What way is that? I'm definitely up for using that when I put them back in tonight.

Astral

The camber cam did not want to rotate down? Did you disconnect the rear swaybar? If you unbolt the rear swaybar brackets (don't bother undoing the endlinks) that are right next to the exhaust heatshield, you can drop the rear swaybar down several inches and you'll be able to easily swing the lower control arms down and make it real easy to take out the rears.

Even if you already have the spring/strut assemblies out, unbolt the sway anyways and drop the control arms all the way to the floor, it will give you much needed room to slide things back in.

When you're putting the assembly back in, the trick is to make sure that you line up all the screws on top, such that the strut goes all the way up into the holes. Once that's the case, have an assistant (wife, whoever) step on the hub to push it down some, which pushes it down enough to let you mount the bottom of the shock.

shaunv74

Yes. The swaybar is unbolted. If it rotates down out of the way then I'll get on it some more tonight and get it out. I just wasn't sure what the range of motion was and didn't want to break anything due to ignorance. Thanks!

Astral

I don't have any pics right now to show you, but in my experience, the control arm that connects to the camber cam swings quite a lot down and has a pretty wide range of motion. Everything should swing pretty easily, without much effort. You shouldn't feel like you're forcing anything. If it doesn't, then something else is wrong or not unbolted. Maybe post a picture of what your disassembled rear end looks like right now?

shaunv74

Thanks for the input all. I completed swapping my springs back to OEM last night. It's so much higher now I feel like I'm driving an SUV.

The clunking and scraping and binding is gone and the harshness through town is definitely better. The shocks and sways still make the ride stiffer than stock but it's clearly more comfy. I am getting it aligned on Tuesday so I'll wait until then to really push it.

I'm definitely happy to see that I don't have any permanent damage and everything seems to be back to normal.

Anyone wanna buy some used springs.

EricMeyer

This is a thread that has yet to get explained and I fear those that are considering the wonderful benefits of aftermarket suspension may have gotten scared away.

Here we go:

-It is possible to buy shoes too small that cramp your toes but the width feels perfect.
-It is possible to buy a suit that is too small with your pants too tight, your socks showing and your jacket sleeves too short. The rest of the suit may fit but PARTS OF IT don't.

In short, you can't assume that one product (like an aftermarket spring or shock) will work with each other. This is the issue. It's easy to see that there is huge coil bind in your initial pictures (as many people have pointed out). The distance of the actual pig tails of the shock is zero. This allows for NO vertical suspension travel. Zilch. You might as well have a solid steel rod welded in there. It doesn't matter that your springs "were designed" for an RX8. Items designed for an any car can have limitations. Think about wheels and tires for example. It is possible to get larger wheels and tires and they (a) don't fit, (b) they rub, and (c) they hit your brake rotors, etc. You have the same thing going on here with your rear suspension. NOTE: It could have been your front suspension as well. It could be both. In your case you offered the rear so let's talk about suspension in general paying special attention to shocks and springs.

I believe your shock body is too short to use those springs OR your springs are too long for those shocks. Again, we are back to the shoes or the suit metaphor.

Here is a quick story that I hope supports my typical paradigm for "custom" parts. This post is meant to inform and educate. It's a Grand Am Koni Challenge story as usual.

Koni shocks N.A. put together a sponsorship package for Grand Am in 2007 to be used for 2008+. They sponsored the 2008+ series for GS and ST cars. Those running Koni shocks are eligible for a contingency (money) when placing well/finishing up front. Given this, several race teams got in line and said "I'm interested in this sponsorship for 2008 and want some Koni's for my car". Since most of these cars are custom (using aftermarket or homemade or stock suspension, modified swaybars, usually lower ride heights, several different spring rates, different bushings BUT NOT CONTROL ARMS and a combination of all the above) an off the shelf product would no suffice. As many of you have learned, there are very few product offerings and those offered usually have with them a customer perception (as seen in these posts) that there may be problems. Welcome to the unique world of a car that doesn't have a huge aftermarket product offering (like the Ford Mustang for example). Naturally, Koni needed to come up with a solution for these teams, part together a drawing and assign a part number to it. Therefore there was something for these interested customers to purchase. The following is a story sharing what our team (and myself personally) experienced. It is my hope that this story sheds light on this "rear aftermarket springs too compressed and clunking" thread. Aftermarket suspension can be wonderful.

Please see next post for the synopsis.

E

EricMeyer

Grand Am Koni Challenge new shock write up.

On or about November of 2007, Koni N.A. did a deal with Grand-Am (involving the GS and ST cars). The series is now called the Grand Am Koni Challenge Series http://www.grand-am.com/koni/

I contacted Lee Grimes of Koni and asked to buy some shocks for my 2005 RX8. The model required (it is my understanding) were the double adjustable Koni 2812. Here is a pic: http://www.koni-na.com/28.cfm

Keep in mind that these are the SHOCK BODIES. These are not RX8 shocks. Think about an 8' wooden 2 by 4. It's not made specifically for a custom house--it needs to be cut to length. Possibly mitered. Possibly drilled. In short, it probably needs modified.

So I call Lee (who refers me to Gordon Benson) and we talk RX8 shocks. Turns out that our friends at SpeedSource got here before I did (it is my understanding that they provided a drawing to Gordon) and there is a part number available. So I buy this part number(s) both front and rear. Imagine my surprise when we install then (along with 10" springs in the front and 8" springs in the back) and they don't fit properly. It was recommended that we use 2.5 I.D. (inside diameter) springs. Click here and "COIL OVER SPRINGS" to understand the variety of springs. Hundreds of custom lengths, widths, rates, etc. We use Hyperco (made right here in Indiana) however there are several other manufacturers that offer the same/similar widths, lengths and rates. Click here and "COIL OVER SPRINGS" and then any I.D. Look at the variety of sizes.

So we get our new fancy 2812's (I think our racer price was about $900 each with springs (custom springs are generally $75 ea. plus or minus). This is each. We install these new bad boys (which have custom ends on them TO FIT THE RX8. For those who may be new to shocks, here is some basic info for our cars: The front shocks go through the wheel wells at the top and connect to the bottom of the big gnarly LOWER aluminum control arm (the RX8 has two front control arms). These are commonly referred to the UPPER and LOWER control arms. Our Koni's fit in the same location as the stock shocks. The shocks had the silver or chrome colored rod on the top of the shock (this would be the orientation of the shock) with the bottom of the shock or the threaded part on the bottom. A bracket was used on the lower portion of the shock to fit into the stock location. Note: The picture I referred to above: http://www.koni-na.com/28.cfm has no ends on it. You can just barely see the adjustors at the very top and bottom of the picture. This is where the adjustors are located on these particular shocks. Some shocks have remote adjustors that have a hose (usually braided steel) and a remote "canister" with an adjustment ****(s). Some shocks have a **** or other mounted on the side of the shock. This is just how they are designed. One is not better than another. Think of an emergency brake on a car---some are located in different positions than the next. All do basically the same thing.

So we get these shocks, install them, use the recommended 2.5 I.D. 10" spring lengths (I think our initial rates were 600 lb front and 500 rear, set the car to an approximate ride height (Koni Challenge series requires the LOWEST PART OF THE CAR TO NOT BE LOWER THAN 3.5"), align the car (I'll spare everyone the details of what a racing alignment includes because I'll lose the new guys and get a zillion questions from guys who want to learn) and to our surprise---they don't fit well. Here were our issues when we first tested these new front and rear shocks at our local track here in Indianapolis: Putnam Park.

During harder cornering, the car had wicked oversteer (like what the drifting guys achieve but no where near the same extent they hang the *** out). We come into the pits, make a few shock adjustments and head out again to run down the Porsche 996's and 997's, corvettes, etc and we still have the same issues. Bring the car in. Take it back to the trailer and get it up on jack stands. Make an adjustment. In this case we raise the right height by turning the adjustment collars that reside on the threaded part of the shock body). We raise the car about 1/2", hit the track and she handles a little better. Hard cornering still results in oversteer. We come in and set the front MazdaSpeed front swaybar to full soft. This is the 3 piece bar that is made by SpeedSource. The rear MazdaSpeed bar was already has no adjustments and basically goes along for the ride in ALL RX8's. This will introduce arguments on this thread but this has been my experience with our RACE car and when interviewing other RX8 Koni teams as well. Several teams don't even run a rear bar. Note: softening the front bar will help the front roll more and typically is a suspension tuning change to reduce oversteer. Basically this reduces some grip in the front which helps adds grip to the rear (to help cure our oversteer). This helps a little bit but there is still a strong oversteer tendency while hauling the mail so we realize something is not right.

Continued in the next thread:

EricMeyer

Continued from above:

Car back to race trailer. Disconnect the front sway bar (to add more grip to the rear). We did this because we were running out of options at the track. Since we're testing and not racing, you tend to try many things----some work and some don't. Out on the track. Same issue. Back to the trailer, car up on jack stands and we stop and regroup for a closer look.

By the way, here is a pick of where the lower FRONT shock mounts to the lower control arm. Note the aluminum SpeedSource swaybar shown in the upper right with 2 adjustment holes showing. The 3rd hole (indicating full soft because it has the strongest lever effect) has the top of the swaybar end link installed in it. We put a cotter pin in there so that we can quickly change the bar when it rains. OFF SUBJECT: When you run a quick release pin like this and it starts raining, removing this pin (so the car has no swaybar) allows the car to rollover more and handle better in the rain. Keep in mind that a race car will run much higher spring rates than a street car (stiffer) and so the car has very little body roll. It's firm. It's planted. It barely rolls. This is bad in the rain. In the rain you want a big, lazy, slow roll to more gently put weight on one side of the car. Think of driving on the ice and how easy it is to turn and have the car start to spin. Slowing the car down when it takes a side load will more GRADUALLY introduce the cars side loaded weight to a slippery wet surface.

Lower front shock mount pic: http://www.ericmeyer.smugmug.com/gal...42850442_ycVgQ

Upon closer investigation, we determine that the rear spring length (back to the first post of this thread) is TOO LONG. When we initially lowered the car to a desired operating height before alignment and leaving for the track (lowered to just over 3" measure at the lowest part of the car---the front spoiler for our car). The upper adjustment of the rear shock (the part that goes here): http://www.ericmeyer.smugmug.com/gal...42846631_oBoWK

has the collar adjusted all the way up into that black tube thingee until we can't adjust it anymore. Our 10" spring is loaded (has tension on it) and what this means is that AS SOON AS THE CAR GETS LATERAL LOAD WEIGHT (from the car leaning over), repeat, AS SOON AS THE RIGHT SIDE OF THE CAR GETS WEIGHT ON IT FROM TURNING LEFT, the rear goes to coil bind. This is the same as not having your springs not able to function like a spring (up and down). This would act as a solid connector from the right rear of the car to the ground. This would lead to not letting the car raise up and down or float. This is like a fixed steel rod from the actual frame of the car to the ground. Forget the shocks, the car is connected directly to the ground in this case. Here is a picture of the REAR lower shock mount of the Koni 2812. Notice the shock is inverted (with the chrome rod just above the black lower perch where the bottom on the spring sits). You can just barely see the chrome rod in this picture way at the top. Pic: http://www.ericmeyer.smugmug.com/gal...42853371_waBLN

Keen eyes will also notice that these Koni's have ends installed on them (remember our 2 X 4 analogy) that thread on to the stock shock bodies to make them fit to our RX8. This would be the red donut with a metal snap ring. Notice underneath that is the adjustment for the rear shocks. This adjustment (for these shocks) is the tiny red donut with holes in it). You stick a thin adjustment tool (like a really think screwdriver without a phillips or flat head on it) and you turn it to the left or right. There are two of these (for compression and rebound), only one is seen in the picture.

The black housing on the bottom on this rear shocks is connected to the post on the aluminum triangular looking rear hub (some people call it a spindle, racers might call it an "upright". Consult your RX8 repair manual (a must buy) for exact description.

So we have these fancy pictures and you'll recall that we had too long of a spring which after several adjustments we concluded that the spring is too long. Back to the shop, order an 8" spring. Repeat process.

Thread continued on next post

EricMeyer

Continued from above:

So thus far we have purchased some custom shocks (turns out that we are the first team to buy these shocks--Koni just had gotten the stock Mazda RX8 shock DRAWINGS) to make a drawing and part number so teams could buy the shock. Our suggested spring lengths were too long (remember the first post of this thread that showed coil bind and next to zero travel). Keep in mind that the user in this post is running very low spring lengths which allow the car to roll easily resulting in zero spring travel.

Back to story. We get an 8" spring length (which by the way we switch over from a 2.5" I.D. spring to a 2.25" because it was easier to get in there and make adjustments (more on that later) and go to Carolina Motorsports Park for December testing. Same issue but less noticeable. Special thanks to my Mazda Spec Miata buddy Tom Long (a very, very fast professional racer) who reminded me (I had forgot) that we can put a tiny zip tie on the chrome rod of the rear shock to measure the travel. To put this another way, we put a tiny zip tie on the chrome rod, drive the car and look at it when we get off the track. First off, on the tight turns of CMP we are again oversteering. Particularlly on exit where the car is just spinning the rear wheels (which makes you go slow). We look at the zip tie and sure enough, the zip tie is at the bottom of the shock. This means that we are running out of SHOCK travel OR our shock bodies are TOO SHORT. A too short of a shock rear shock body in our example is the same thing as making that direct BODY TO GROUND connection and like our driving our ice metaphor, the rear end can't freely move up and down, the car loads the ground way too hard and there is no give and the rear wheels spin. Prior to this we had switch to fresh Hoosier Grand Am slicks (which reduced the problem a bit), tried adjusting the shocks (which helped a little bit) and lowered the front end way too much (to take some weight off the *** end to help get more grip). The end result? We figure out that our rear shock bodies are too short. We are running out of travel at desired ride height.

Hopefully this story thus far as shed light on some things that can happen when being the first to buy and try a shock. Looking back it was a great learning experience that told us (and me in particular) a ton about shocks.

Back to the shop. Call Koni. Explain the symptoms along with all the things we tried. They conclude that the shock bodies are too short (remember, we were using pretty stiff springs in our testing so the potential for the car to easily roll over and run out of shock was much less than if we were to running a street spring OR MANY OF THE OPTIONS CURRENTLY OUT THERE AVAILABLE FOR THE RX8. THESE OPTIONS ARE STREET SPRING AND PERFORMANCE STREET SPRINGS. THEY ARE VERY FAR AWAY FROM A RACING SPRING WHICH YOU USE TO MINIMIZE BODY ROLL.

Receive and install new rear shocks bodies (there is nothing like getting new goodies for your car). In this case Koni used our shocks and REBUILT them using the same bodies but with a LONGER rod. This effectively lengthened our shock and saved us a bunch of money. Note: Higher end race shocks are can often get rebuilt. There are three high end professional race shops here in Indy that do this specifically. Pro race teams do this often. it is normal. "Wow" you say? Yep. Again, this is the purpose of this post---to share what happens at the racing level and expose interested readers to a world outside of limited (but often good) product options. In our case we are striving to build the best shocks for a RX8 unibody car. (I think we've done this by the way---read one).

So we go to VIR and we are passing so many people I feel like Payton Manning Quarter backing at a Jr. Varsity football game. The car is rockin. We easily win our NASA class and make a huge charge in the rain for the 3 hour enduro. Something like 12th to 2nd before our fuel hungry RX8 starts to fuel sputter.

Are we done yet? Nope. Back to the shop. How do we improve on our design.

Currently our adjustment collar (the part that the top of the springs sits on) is very close to that black tubular thingee that resides in the trunk and is installed from the bottom of the car. Again, shown here: http://www.ericmeyer.smugmug.com/gal...42846631_oBoWK

The problem is that when we run at our desired ride height (to have the car as low as possible but above the 3" minimum ride height) our effort to adjust this collar (black in color) seen here about an inch on top of the blue spring HAS US RUNNING OUT OF ADJUSTABILITY. Our shocks are now too long. Seen here:

http://www.ericmeyer.smugmug.com/gal...42851716_VYGwU

Sharp eyes will notice that the bottom of the black adjuster (which determines your ride height) is running out of threads. Notice underneath this black collar there is next to zero threads showing which limits our ability to lower this collar (which would increase our ride height). Essentially when you turn these rear collars so that they travel DOWN the threaded shock bodies, you are LIFTING the rear of the car.

Do some measurements. Back to Koni where they rebuild our shocks and we get it exactly right this time. What is exactly right? Well according to our boy Gordon, you want a 50% compression and 50% droop IN THE REAR for your shock. Here is now you measure this:

Set the car to desired ride height (contrary to popular opinion, shock settings don't mean squat when you do this) so the comment about the coil bind on this very first post and where the shocks were set is bogus. Put the car on the ground. Measure the chrome rod length with the car on the ground. In our case the length of the rod was/is 3.25". Now jack the rear of the car up. Measure the ride with the car in FULL DROOP. In otherwords, the suspension is hanging down and the shock is hanging. 6.5". Excellent. Buy luck our droop to compression ratio is 50%--just what we were told we need.

Note: We have 3.5" of travel in the rear. Take a look at your measurements for comparison. Please understand that this is not a desired target for your application. It is just a reference to say "wow, that's not alot of travel". Correct. Remember, we run way more stiff springs. 3x more that street cars in some situations. 2x more in most applications.

Almost done here.

Because we are running out of adjustment shock body thread. We move to a different LENGTH of spring which gives us enough adjustment.

Summary:

-At desired ride height our car has a 50% compression to droop relationship (the shock is right in the middle of it's travel range when sitting static on the groud.
-We have a great spring length which allows good adjustability.

Now we go buy a bunch of springs in approximately 50 lb increments.

For the rear: 300 to 600 in a 7" length (this is that we have determined works best for our application). 400 to 750 front in 9" (best for our application but highly unlikely it will work for yours).

All done. No more. Apologies if I've made an error in this story. I did my best and my typing hands are tired. I hope this has shed light on this post and helped current and future users fix and/or avoid future problems. Keep in mind that some companies DESIGN A SHOCK AND SPRING TO WORK FOR A GENERIC APPLICATION. As you've seen in this novel, lots of factors came into play for us. Lots of rework and tuning. Lot s of testing and measuring. If you don't know how to do this and more importantly (IF YOUR SHOCK DOESN'T HAVE ADJUSTMENT OR ROOM FOR ADJUSTMENT) you are S.O.L. Often the resellers of a shock are not in the business of custom making a shock that is designed for a specific application let alone when a customer might choose to modify it's application. The story referred to above is for CUSTOM RACE SHOCKS where it is NORMAL to adjust, rebuild, revalve, shorten, lengthen, put the rod on top, put the rod on bottom, change the mounting bracket or heim joint, change the length of the mounting threads. Lots of custom variation.

Please feel free to contact me with any questions. Ultimately you need to get under your car and look, think and look again. Most problems can be figured out by having a couple of your smart buddies (Mechanical engineers are good at this) look at your situation. Don't feel hesitant to contact CUSTOM shock manufactuers (like Koni) to help you figure out your situation.

Best wishes and happy custom suspension tuning.

Eric

meyermotorsports@mac.com

Eight

iTrader: (2)

wow interesting read, but way too advance for me.

so is there any follow ups about the faulty espelir springs? did you get any message back?

shaunv74

Here is my Summary:

They were great with the stock hi pressure shocks.

they did not work properly with the aftermarket Koni low pressure shocks.

I think they are not designed to work with non-high pressure shocks so if you get them stick with a set of high pressure shocks such as the Tokico's D-spec or stock.

My best advice I can give you is to make sure you buy a proven shock/spring combination. Find someone on the board that has the combination you are looking for and ask them how it is working for them.

I purchased a pair of Swifts and am going to put them on as soon as I get a free weekend and see how they work out with the Konis.

EricMeyer

IF you torque (to manuf. spec) the control arm bolts (the two for the upper A and the lower front bolt---for camber) you most likely will get something called "stiction". This is a pretorqued bushing. This is assuming you're using the stock bushings. The nature of the stock bushing is to twist/flex/give/perform a bushings duty when it is torqued IN THE NORMAL OPERATING RIDE HEIGHT. Therefore, DON'T let you suspension droop when you torque it down---both front and rear. Make sense? This can and will explain how the suspension doesn't freely travel vertically.

Happy torque'ing

EricMeyer

Help me understand this please. My gut says that the pressure of the shocks has nothing to do with fitment. Typcially there is no ride height differences due to pressure. If you had a broken shock this very well could be different. You would have to give it a big bottoming out to break it and the broken corner/corners would ride at a lower ride height.

I beleive this goes back to improper matching of components which happens all the time.