Hi guys,

I just started auto-xing my Evo and I need some major help in sorting out the suspension. I have been auto-xing for about 4 years with a rear wheel drive car, but now I can't figure out my AWD set up. I have searched and I can't seem to get a definite answer for my questions.

My car has the following:
- Race Comp Engineering springs
- Perrin rear bar and end links (set on medium)
- rear strut bar
- Stock shocks (thinking of replacing), have 40,000 miles on them

My Problem - the car understeers like crazy on initial turn-in, but it has really good off-throttle, mid turn rotation. I just can't get the initial understeer out, and it also understeers when I am on the throttle coming out of a turn (which I expected, but I want to reduce it if possible).

Question 1 - tire pressure. Some guys recommend more front pressure and less rear to combat understeer. Others say the opposite. I thought it was add more to the front to lessen understeer, but can someone clarify. I ran 36 front / 32 rear on Nitto Nt-01's. I know nitto's aren't the best, but thats what I have now and I can't afford A6's yet, but they will come soon.

Question 2 - I am thinking of replacing my RCE springs with Swift Spec -R's. Are the Swift's any better? I couldn't find specs on the RCE's and they were in the car when I bought it. I can't afford coilovers, so I thought the swifts would be nice based on other people's comments.

Any ideas on my car set up / sping question?

Thanks.

 

I forgot to mention that I an running -1.8 camber front and -1.2 in the back.... I was thinking of getting a set of Works camber plates to run more in the front and combine the plates with the Swift springs and possibly new shocks depending on price.

 

A1: More tire pressure in the rear. I run 34/36 and go from there.

A2: Struts would help if the OE are worn. Spring differences:

GTWorx (RCE Springs): 290, 330. -0.8, -0.6 drop
Swift Spec R's: 157-358, 196-380 (153-380 for MR). -1.4, -0.8 drop.

Spec R's are stiffer at the limit than the GTWorx, both are great.

I would add a front sway bar. It helps a ton.

Here is my car with Z1's (original Z1's in the video 34/36psi, -1.6/-1.4 camber, Swift Sport springs, and Swift front and rear sway bars)

http://www.youtube.com/watch?v=EwW8i3JqxjQ

(sorry youtube removed my sound... )

 

Run the rear sway at full and try more rear tire pressure. Camber plates would help in the front so you can get -3 ish on the camber.

 

All good advice.

Definitely too low on the pressures. I run NT01's on the roadcourse and strive for 38-39 hot. More front camber wouldn't hurt at all.

 

thanks for all the advice guys! I will bump up the tire pressure and make the sway bar adjustment. Also, I think I am going to do the springs and a new set of struts. I might as well just do it all right once rather than have to add struts later

 

You'll need about -2.7 to -3.0 camber up front and around -1.5 in the rear. The tire pressure changes will work until you can fix the suspension properly. More rear bar adjustment will help a bunch. A heavier front bar will help since coilovers are out of your range right now. The less spring you have up front the more negative camber you'll need so you may need to go to more than -3.0.

You can lose the rear strut bar, it's useless in an Evo unless you need it to hold remote resiviors for coilovers. You have a multi link rear suspension so you don't need the bar unless you are trying to add weight in the rear.

 

Dave - thanks for the advice. I didn't even think about removing the rear strut bar

 

If you autocross in the Philly region you should go talk to Corey Ridgick or Cy Lee or Adam Fuhs. They are the fastest Evo's in the area and they'd help you a lot.

Dave