WRX suspension trivia

[Bart]

All,

When comparing total effect between the STI, STI RA and STI lowering springs, is the lowering and the increase in spring rate a compound effect?
In other words, can I compare just the spring rates or when considering the lowering springs, is there an additional increase in stiffness due to the lowering that is not accounted for in the spring rate?
Thanks,
B

[vano]

Good question Bart.

Also, as a follow up to that. Are the STi Adjustable shocks built with Lowering Springs in mind?

Im asking because they are both the same color pink and are often sold as a spring/strut set. If so, does that mean that going with STi regular shocks and keeping the car 1 inch higher than with Lowering springs would take the Adjustables out of their optimum operating range?

I know 1 inch isnt all that much, but it could still take the shock out of its optimal opearting range.

[GV27]

I believe the struts are not position sensitive.

The spring rate shouldn't be any different due to the lowering - but you are likely to hit the bump stops more often resulting in a rougher ride with shorter springs.

[Big Sky WRX]

Lowering will not have any effect on spring rate as GV27 mentioned, it does lower the center of gravity which has it's advantages (also disadvantages as well- loss of clearance etc).

The Sti sport (pink) springs and struts were designed to work together, but the sport springs will also work w/ the RA/STi struts as will the STi or RA springs work w/ the sport adj struts.

I think it really boils down to do I need (want) lowering (sport springs), do I need adj damping (sport struts), do I want close to oe height and spring rates slightly above stock (STi) or higher yet (RA).

I think any possible combination will work, it depends on your needs which one to go for.

Don't forget tops in the equation- I think the hardened Group N tops compliment any of the above combinations.

Big Sky

[csacom]

Wow, so many choices! And so many threads. I am hoping maybe someone can steer me in the right direction. I have a 2003 WRX that I would like to upgrade the suspension on. I do not want to alter the current height. I am loooking for a setup that can reduce the current body roll, while allowing for driving on rough roads. I have been looking at the SPT/STi Performance Suspension Kit, but I am worried that it will bounce all over the rough road. Any ideas or experiences you can share with me?

[KanosWRX]

The SPT suspension is the Type RA suspension. I have it on my car and it is more bouncy then stock, but thats what happens when you get higher performance suspension parts. Its not really that bad though, most people wouldn't be able to tell the difference. I really like it as it keeps close to the same ride height, as it only lowers it about 1/4 of an inch, but it makes the car feel so much better and less floaty.

[Big Sky WRX]

Originally posted by csacom
Wow, so many choices! And so many threads. I am hoping maybe someone can steer me in the right direction. I have a 2003 WRX that I would like to upgrade the suspension on. I do not want to alter the current height. I am loooking for a setup that can reduce the current body roll, while allowing for driving on rough roads. I have been looking at the SPT/STi Performance Suspension Kit, but I am worried that it will bounce all over the rough road. Any ideas or experiences you can share with me?

The SPT kit (RA) for the sedan will work fine for gravel, but leans a little towards tarmac (rates of 217/192). If you see a fair amount of gravel, look at a takeoff set from a "normal" STi sedan- uses exact same struts, but reduced rates of ~ 180/170. This would be a nice compromise between oe (which does very good on gravel, but poorly on tarmac) and the RA setup which will work on gravel, but shines on tarmac.

Big Sky

[GV27]

I was referencing this thread for a member and thought it might be a good place to add v.8 info since I have this thread referenced in the tech. reference sticky.

So have at it - whadda y'all know about the v.8 STi options?

C

[Big Sky WRX]

STi v8 sway bars are 20mm and 20mm (change from 19/20)

spring rates are ~ 188/173-rear springs are tapered and utilize a newly designed top- they also lower by 10mm

caster- almost a degree added 4.5 due to design of front control arm, slight increase in neg camber front -.25-> -.30

brace between the front control arms, increased bracing in the front cross member

slight change in mounting point of front trailing link

different rear sway bar w/ pillowball sway links (utilizes a different rear lateral link to accomodate the mounting of the links)

Those are the highlights

Big Sky