New suspension choice for ST/SP/SM RX-8s: http://www.tirerack.com/suspension/s...712&perfCode=A

*ignore that the pic is for a Corvette, they have these for the RX-8.

I have not been able to get the spring rate info, Eibach wont give it out, but the good news is you use the standard 2.25" ERS springs and can change them out. I have a call in to one dealer I know and he thinks he can get them built to spec with any spring you want. These are the same units that were on the SCCA Pro-MX5 cup cars last season. No idea on the dampening quality of the Eibach shock, I wonder if they outsource it, but it is a real double adjustable.

 

that's the same as the Mazdaspeed coilover kit and it is single adjustable only

 

That is not what Eibach says...

http://eibach.com/cgi-bin/htmlos.exe...17029300032386 *again this is the Corvette system but they do have it for the RX8/MX5.

This is the system that was used on the Pro MX5 cup cars, and those were doubles. As cheap as they are I wonder about the quality.

 

ok, maybe my bad then

but for $1250 I wouldn't expect anything sophisticated i.e. needle valves for valving adjusters ...

 

Right... The springs are easy. So the only place to save money on the kit is the shocks. I would like to hear what the MX5-Cup guys think of them. I also wonder why Moton is the spec shock for them now.

 

followup, that's a mistake by TireRack, it's not the kit as shown, it's the same coilover single rebound-compression adjustable coilover kit as what Mazdaspeed sells

as a comparison, the remote canister Callaway coilover kit shown for the C5 Vette sells for $2700 as compared to $1250 for the linked RX-8 kit

 

I have been doing some research on coilovers and am far from making a choice but the ones that I am looking at are the cusco's , KW variant 3, Blistien pss9 and on topic these Eibach's (which from what I gather are the same as the mazdaspeed's as pointed out by TeamRX8)

It seems that these are the Multi-Pro-R1's. So they are not the R2's that have a remote reservoir and have separate adjustable for rebound and compression. And they are not just adjustable Pro Street's that is suggested on their web set. Unless the Pro Street are mono tube then I guess they would be, but they don't state that on thier site. You can check this out http://eibach.com/eibach/img/eps-17catalog.pdf Pg10 & pg53.

The thing I like about these are the ERS springs. None of the others offer that type of option.

Anyway just wanted to throw this info out there.

 

So my research continues and it seems that the Mazdaspeed Coilovers (which I think are the same as the eibachs ) run a 8 inch 2.5 inch ID ERS spring with 400lbs/in up front and 275lbs/in on the rears.

Pg. 4 & 6. List the part #'s of the springs. 800.250.0400 & 800.250.0275 http://www.finishlineperformance.com...AZDASPEED).pdf
If you look at the Eibach ERS Cataloge Pg. 16 & 17 It gives you the rates.http://eibach.com/eibach/img/ers-catalog-2004.pdf

What is surprising to me is that the few reviews on these coilovers the owners state there is very little or no increase in stiffness with these coilovers over their OE set-up. While these part #'s confirm that they are over twice as stiff from stock. Is this a great coilover or is the above info just wrong? At any rate if these #'s are correct these also are the closest to OE front and rear spring rate ratio.

 

I'd agree with your find on the rate #s, good catch.

 

I wish those fit the FD

 

I've been looking into a coilover kit for NASA's TTD class, and the Mazdaspeed coilover looks like it might be a better choice than a koni+aftermarket spring. Are the koni SA's valved for a specific spring rate range? From what I've seen, those spring rates are lower than what'a available with the MS coilover kit.

 

dude, that shock isn't even remotely comparable to a Koni twin tube for competition use

 

So whats the stiffest spring you can run with a Koni? From what I know there aren't any springs stiffer than 300 lbs out there for the RX8.

Is this true? If so I think they would be comparable. But then again most people around here seem to swear by koni's.

 

The rates could be an issue depending on your specifics.

I'm pretty sure that I can convert the Koni's to be coilovers. Nobody has done it yet because the rear shock tower design complicates mounting the rear spring with the shock in the normal upright position. You can't invert these particular Konis because they're a twin-tube design. The front is no problem, very easy.

My problem is time, just haven't been able to get to it.

The Pro MX-5 cars all use the same Spec parts i.e. no competition between brands. That's like Toyo ballyhooing that their tires won a championship which required their spec tire.

 

Pro Parts had a set of Koni Yellows I saw sitting on a work bench with a coilover conversion done. I didn't pay much attention to the rears though.

 

That's very possible since they specialize in custom work, thanks.

 

I explored converting the Koni yellows a while back. Truechoice quoted me a price, but for how much it was - the guy basically stated I should just spend the money and get a 28 series damper instead to my desired specs.

 

I don't think I was ballyhooing.

All I meant is that these are similar to the koni's because they are street shocks by reputable companies that have been used in a competition environments in a specific series.
Which one is better I don't know. As of yet no one offers any coilover conversion for the koni's on the RX8.

 

ideally you'd want to convert the rear shocks from internal to external adjustable to avoid disassembly for rear rebound adjustment, but there's no way this setup should get anywhere near the $1000 each 2812 price (which doesn't include springs, spherical bearing top mounts, etc.)