I don't understand the physics but according to Dick Guldstrand, a car that has had the center of gravity lowered will have the roll center below ground level. This adversely affects front camber when the wheel/tire are under load and reduces tire contact surface. To increase tire surface contact area Guldstrand has a simple fix for Camaros and Firebirds to relocate the upper control arm mount 0.75" lower. The F-body towers allow this by drilling a couple of new holes. Guldstrand provides a template to locate the holes. Apparently the Shelby Mustangs have a similar fix. I looked at the C3 towers. I don't think space permits drilling and lowering the control arm. I would not be surprised that someone has thought about this and come up with modified upper control arms or cross shafts to accomplish the same thing. For example, a cross shaft that has offset bolt holes would effectively lower the control arm. The control arm would need (I think) to be ground down to clear the chassis when in the lower location.

 

On camaros mustangs they raise the upper control arm
mounting point not lower it. When the 70 camaro came out they
raised the upper control arm one inch in comparison to the 67-69.
Carrol Shelby raised the uper mounting point on shelby mustangs.
I would think offset cross shafts change caster angle not camber??
There are uper control arms available for camaros with a lot more
caster bult into them and there are taller spindels availble to match
up with the raised mounting point of the upper control arm. These
are available for cars that have been lowered to help get back the
original geometry designed into the car.

 

You don't drill new holes in the towers.

 

I thought you would want to lower the inner mounting point.
I went to custom long spindles to do the same thing.

 

I think he's got it backward

 

lowering the Cg does not affect the roll center, the roll center height is a product of the suspension angles (instantaneous center), the car's centerline and the center if the tire contact patch. Changing the suspension angles, lowering the car, that sort of stuff changes the roll center.

A low roll center promotes body roll, a high roll cneter decreses the amount of roll induced by weight displacement (pole vaulter analogy, where the pole vaulter sticks his pole...if low/on the ground the pole vaulter will lift himself, high he won't)

There's a catch though, you have to discriminate between from=nt and rear suspension and thus the front and rear roll centers, they are not the same. If you fint he 2 you have the roll axis. For the rear a roll center that is too high will induce a jacking effect where the inboard tire jacks up the rear (same pole vaulter analogy) and this gives pso. camber change and reduces the contact patch also.

Lowering the upper cross shaft will give a more aggressive camber curve, however it'll also make the upper arm "shorter" (horiz. component) and this means that you may end up having problems setting proper static camber.

 

On 1st gen f-bodies and early Mustangs you lower the upper control arm mounting point because they have an incorrect camber curve stock. 2-nd gen f-bodies as well as C3s have a good camber curve stock so no need to move anything.

 

He has it backwards. You want to lower the inner mount NOT raise it. If you can't lower the inner mount you raise the outer ball joint. To do this you need custom long spindles.

 

If you have what your name is: 7T3C3TTZ07

Your have to get down to the local road racing track and talk to the real lapping cars mechanics. There is alot more to it depending on how ridged your frame is.

 

Yep I think your right I have it backwards