MKIV front end suspension numbers

[skullandbones]

Hi techs,

What is the KPA/SAI on the MKIV roadster spindle?

I don't have a MKIV manual but I suppose there are published recommended alignment numbers. Can you post those? Are they any different for the manual and PS setups?

Do any of you have the static roll center, CG, etc. with the recommended ride height? I'm guessing 4 inches is still recommended ride height.

Thanks in advance,

WEK.

[skullandbones]

Tony. Anybody.

From what I have heard on suspension threads, FFR has done their due diligence on the redesign of the MKIV front suspension geometry if you use the new spindles and related components. So how good is it? I'd like to see the hard data.

Thanks,

WEK.

[CHOTIS BILL]

I am not sure if the coupe and roadster have the same geometry or not but I measured my gen II coupe with the FFR spindles to come up with some numbers I believe are close. The only number I received from FFR was the roll center when the frame is setting at 4” ground clearance. I used Bill Mitchel suspension program to do the calculations and the calculated number for the roll center came out within .002” so the pickup points must be pretty close.

My numbers are:

RC = 3.262

KING PIN ANGLE = 13.839

IN. CENTER LENGTH = 88.891

IN. CENTER HEIGHT = 10.000

SVSA LENGTH = 0

SVSA HEIGHT = 10.00

Bill Lomenick

[skullandbones]

Hey Bill,

Are you surprised that the SAI/KPA is as high as it is or not? I thought that would be much closer to 9 degrees or even less (race car like). I can see that my ~7.25 RC is too high so I guess I will have to make my own LCA mounting holes like David B is doing or has done. That should get it down a bit.

Thanks for you input,

WEK.