I've got an '89 GTUs and i'm running KYB AGX's for struts and eiback springs (pro kit). I like the set up because its an upgrade from stock and its still streetable. I'm about to buy some Yellow Koni adjustables and some RSR race springs. I'm probably gonna run the Koni's for struts but which spring should i run on my car? Note that i want the car streetable still and i want to run it on the AutoX. any input/help would be greatly appriciated. if it helps the spring rates for the eibachs are front: 70/185 and the rears are 85/165. i was told that the RSR's are front 335 and 224 for the rear.

Thanks in advance,

Izzy

 

I have ground controls on tociko blues, and the spring rates are right around 325 F 250 R (or pretty close) . Its perfectly streetable, and a HUGE improvement over stock at auto X. But after a while you'll get used to them and start noticing more body roll.

Fortunately Koni's are re-valvable so if you want to go w/ a stiffer spring later on, you'll have that option.

 

thanks

 

Don't forget swaybars. You can get away with a softer spring rate if you go heavier on the swaybars, and it won't have such a negative effect on the ride comfort...

 

It will have a negative effect of picking up the rear at corner exit though, which is no fun depending on which (if any) diff you have. I always was told sway bars were more of a fine tuning thing.

The RSRs are going to be about the stiffest factory-perch spring you are gonna find. Spend the money and get ground controls, probably in the 400/300 neighborhood to start with. Its still fairly streetable and will transform the car through the cones. If you run r comps, you might want to go even high, the Konis are functional up to about 500 lb/in with stock valving.

 

well looks like the koni's and RSR's aren't gonna happen, the guy sold them out from under me. so what are some suggestions for my current set up? KYB AGX's and the Eibachs. also have a cusco rear strut bar installed because it helps my rear hatch from flexing. right now i'm running my stock GTUs wheels which are 16X7 on some 225/50/16 Potenza RE-01R's

 

bushings and camber (at least n the back)
and drive a lot.

 

sorry forgot to mention that i have a mazdatrix rear camber adjuster, i should probably buy a bushing kit.

 

I went w/ the AWR independent rear camber adjusters, can't give you any useful info yet, because they aren't yet installed :-(

 

^ keep a close eye on the individual adjusters! one of mine wouldnt stay tight, and would 'adjust' itself after a while. i had to take them apart and use more jam nuts.

 

hmmm....perhaps a little loctite is in order?

BTW, aren't 225's a little wide for a 7" wheel?

 

they seem fine. i did have to use a slight spacer up front tho, to keep the tire from hitting the springs. i didn't need the spacer out back, but i installed them none the less.

 

WHAT?

The correct wheel size for a 225 tire is 7.5" or 8". It produces the largest contact patch.

 

As long as the front bar is also stiff enough, you won't get the rear wheel lift on exit. And if you have an LSD then its not much of an issue anyway, but with a heavy front bar the car will be better balanced overall. At least, this is how it worked out with my car, which is a 1st gen.

 

I'll have to keep this in mind and maybe buy a new sway bar up front

 

(not 7")

kinda what I was thinking....

I'm sure the clearance is fine, especially since you have spacers. But 225's sorta bulge on 7" wheels, more of an asthetic thing than anything really.

What kind of bushings are you looking to get?

 

looking at maybe a master bushing kit from energy suspension, and then also upgrade motor and trans mounts too. not solid tho.

 

protip: poly rear control arm bushings + individual camber adjusters = no bueno.
if you get the indiv camber links, you either need OEM bushings or sphericals from AWR/MMR. its a multiaxial pivot point, and a poly bushing only swings one way.

 

^ So I have read on the website, looks like some of those spherical bushings will be on the agenda down the road...unless they require machining of the subframe...

I just got the MMR tranny mounts, and passanger side motor mount installed. the passenger mount was completely sheared in two, turns out there was no underside nut on the driver side mount lol.

Surprisingly there isn't an increase in vibration at idle or really at highway cruising speeds. Its mainly in the higher RPM's in lower gears (1,2,3, above 4k). And I'm not entirely sure that's not drive shaft related anyway. The car feels 20x better when driven purposefully, and is tons more responsive. Guess I'll have to update whenever I get that driver side mount in...

 

so over the weekend i installed a set of energy suspensions front control arm bushings, tie rod and ball joint boots, and front sway bar bushings. the car has a better road feel and the steering feels firmer. haven't done the rear control arms, because of the amount of stuff that has to come out.

 

dont use Energy's rear control arm bushings! the only place poly should go back there is in the hub (DTSS elim, and the other two bushings which no one makes).

Rear control arm should be OEM or spherical bearings only

 

alright i wont install the rear control arm bushings. why shouldn't i use poly bushings back there? if you wouldn't mind answering this for me.

 

because if you install poly RLCA bushings, you won't be able to adjust camber when you lower your car. At least not witht eh independent rear adjusters, I'm not sure if the single center mount camber adjuster has that same stipulation.....

 

The single adjuster will be affected if you use stiffer subframe mounts. For adjustability's sake, you'll need to use spherical bearings on the RLCA's to avoid binding. That is, if you are to run the individual camber adjusters.

 

I'd figure that you would benifit more from stiffer subframe bushings than stiffer RLCA busings, so it would appear that individual adjusters are the way to go...