I agree completely. I don't think more than 50% of roll stiffness should come from bars. It'll be better if they increase both springs and bars rates equally. Maybe there is a corporate limit on suspension frequency at GM that I don't know about. Wouldn't it be cool if fbodfather comes in here and answer some of these questions?

End link studs are same 10mm.

One is listed as an SS and 1LE part number while the other is 1LE and ZL1 specific so something isn't right. Why would only one mount be different?

Actually pal not so at all. Even the Pedders ZL-1 bar isn't so bad. I now have the ZL-1 stocker in the rear of my car and even with Pedders stiffer swaybar bushings the car handles very well and still has compliant suspension. No twisting, breaking my rear motions going on when I pull into gas stations sideways.

It shouldn't be, both were supposed to be ZL1 mounts when I got the numbers. I asked to have them verified because somethings just not right.

Ok, someone else posted on another thread that they were larger 12mm studs. Thanks for clarifying.

Nice cant wait to see what it will take to fit the rear dampers on my 2010 SS.

On any end of a car that provides both acceleration and braking there are two 'anti' effects, not just one. One deals with geometric resistance to suspension movement under braking, the other during acceleration. Unfortunately, in what I'll call "simple" suspension arrangements*** it is not possible to tweak one without affecting the other, and it is common for improvements sought by increasing one of the anti's to adversely affect the other one on that axle.

Up front, anti-dive is normally present for various reasons, and this forces some of the forward load transfer to go through the front suspension linkage directly. This fraction of the forward LT does not cause or contribute to nose dive, and happens almost instantaneously (does not have to wait for springs to compress or damper pistons to reach some velocity). The flip side is "anti-rise" - anti-dive's sometimes evil twin - and when the force at the contact patch is for acceleration rather than braking, some portion of the vertical tire loading is yanked away without the suspension being allowed to extend to fully compensate. This obviously lowers the total amount of front grip available, and then you're going ahead to use some of what's left for longitudinal acceleration so lateral grip suffers . . . you'd then expect that by removing some of the anti-dive you'd reduce the power-on understeer by the difference in the geometric effect.


FWIW, the same sort of thing goes on at the rear axle, with anti-squat having its evil twin in anti-lift. Most people who have autocrossed certain years of LS-powered 4th Gens know more about brake hop than they probably cared to, and anti-lift is part of that. You still have both of these anti's with your IRS, but it's unlikely that a 5th Gen is going to get into brake hop.


*** You'll find some "not-so-simple" suspensions, where the anti effects can be separated and more or less tuned separately. Mostly you'll see this in places like dirt track racing, although Unbalanced Engineering at least used to offer a "decoupled torque arm" for the 4th gen cars. There is some cost in both mechanical and setup complexity, and there may be other compromises as well.

Mark Ortiz sends out a free "Chassis Newsletter" on roughly a monthly basis that covers topics such as this.


Norm

Not sure I'm following this, unless you're talking about correcting the rear geometry.


Norm

All you should need is the dampers and shock mounts. You'll only need to change the rear control arm if your changing sway bars as well. Then getting the new toe links is up to you.

Correct rear shock mount part numbers posted. $49.01 each.

Thanks for clarifying it. I enjoying learning these things.

I was referring to the front lower control arms and front radius arms. I believe BMW 3 series also use double ball joint MacPherson strut design similar to Camaro. Is there any advantage to this design? Looks like it increases the kingpin inclination angle and move dave point out. I am guessing better on center steering feel and straight line stability are the benefits.

corrected on price list as well, thanks.

that makes more sense!

GM PART # 25954415
CATEGORY: Rear Wheel Hub/Knuckle

We only need 2 of these. They are expensive though. I wonder why they are different from SS. To connect to the beefier 1LE and ZL1 axle? Will I still need this if I don't upgrade the diff and axle? nak3dsnake thanks for putting this list together.