Caster

[Mean 69]

Are you using the stock spindle - assuming so? As David states, there is interaction that should give you pause at going really steep with the caster angle. In addition to the increase in caster in dive (which can create in addition to other issues bump steer), the stock spindle is rather short, and it's effective length further decreases as you increase caster, which compounds the problem - although slightly could very well be detrimental. Have you thought about an adjustable UCA instead of changing the mounting location?

Mark

[cornfedbill]

Are you using the stock spindle - assuming so? As David states, there is interaction that should give you pause at going really steep with the caster angle. In addition to the increase in caster in dive (which can create in addition to other issues bump steer), the stock spindle is rather short, and it's effective length further decreases as you increase caster, which compounds the problem - although slightly could very well be detrimental. Have you thought about an adjustable UCA instead of changing the mounting location?

Mark

Thanks for the reply.

I am using the stock spindles. Yes, they are very short. Based on the modifications to my subframe, tall spindles would necessitate raising the upper control arm pivot quite a bit.

I have given some thought to SPC adjustable upper control arms. I am a bit hesitant. They are good quality. But am concerned about potential breakage. I have heard of them breaking under street duty. Potholes in Michigan can swallow a small car, and are known for damaging suspension components. I am still looking at options.

Thanks for your input.

[Mean 69]

I don't know if the breakage stories are myth or reality. I'd do some things different with an adjustable upper arm personally (and am, for different application), but the basic intent is there. Having grown up in the Chicago area, I know first hand how the roads are in the Springtime!

Goes without saying, but if you plan on doing open road racing, safety is paramount with every detail. Horsepower is easy to make these days and as a result one can build a blindingly fast car, and things can go wrong in very short amount of time. Full cage, fire system, etc. Don't shortcut.

Good luck!
Mark

[cornfedbill]

I don't know if the breakage stories are myth or reality. I'd do some things different with an adjustable upper arm personally (and am, for different application), but the basic intent is there. Having grown up in the Chicago area, I know first hand how the roads are in the Springtime!

Goes without saying, but if you plan on doing open road racing, safety is paramount with every detail. Horsepower is easy to make these days and as a result one can build a blindingly fast car, and things can go wrong in very short amount of time. Full cage, fire system, etc. Don't shortcut.

Good luck!
Mark

Thanks Mark.

We will have all the safety equipment. One because I want to protect myself and my son who is my navigator, and also because they won't let me past the tech inspection without it.

I have seen photos of a broken SPC arm. I have also seen cars on the road with them and no issues. I used to live just up the road from them in Colorado before moving back to Michigan. It may not be a bad idea to revisit the idea. It would sure make adjusting things easier than the stock style pivots and shims.