I have a question for the suspension wizards out there. When I was lowering my C5 I went the route of removing the top A arms and dropping the assembly down.

When I removed the 4 bolts from the attachment points to the frame on the PASSENGERS side I noticed I had 1 washer under each bolt of the front “Y” and none on the rear “Y”.

On the DRIVERS side I had 2 washers under each bolt of the front “Y” and none under the rear “Y”.

When I was getting the alignment done the guy said I was out of adjustment capability on the DRIVERS side. Luckily I was at O.O camber already (runflats). He said I had a lot of adjustment on the PASSENGERS side (the one with 1 washer under each of the front “Y”).

He said when I do my brakes, on the DRIVERS side I might want to put 1 more washer under each of the front ”Y” and add 1 washer under each of the rear “Y”. Effectively moving the upper A arm outward 1 washer width to allow more adjustment capability in the future.

Does this sound correct ?

By the way, here are my alignment numbers I had AFTER lowering and then after the new alignment. If you don’t think you need to do an alignment take a look at these numbers.

The chart obviously doesn't post well, but you get the point.

Front
left right
now B4 B4 now


0.0 -1.5 camber -0.5 0.0
6.7 7.4 caster 7.2 6.7
0.02 0.21 toe 0.01 -0.02


0.0 -1.0 cross camber
-0.2 0.2 cross caster
0.02 0.19 total toe


rear

-0.2 -0.6 camber -0.7 -0.2
0.06 0.15 toe -0.05 -0.02


0.01 0.10 total toe
0.06 0.10 thrust angle



[Modified by team5150, 1:35 PM 8/27/2002]

 

I noticed the same thing with the washers on mine. I think I even had none on one of the sides, but I will have to double check. The shop that did my alignment didn't mention anything about being out of adjustment capability. I don't have my exact numbers in front of me, but I started with a lot of positve camber after lowering and putting on wider tires. I opted for a slightly more agressive setting than the standard Z06 and they dialed it in perfect..

 

Don't worry about the number of washers or where they are. This is one of the few cars that provide some adjustment on the top and bottom control arms if you need it. Don't add any washers anywhere unless you intend to get another alingmnt done. Adding washers will change your current alignment. You really only need to change washers (add or remove) on the wheel that has no adjustment left on the lower control arm. By doing this, you can get some adjustment capability on the lower control arm.

 

I will be getting some new tires soon (probably Yoko runflats) and I would like to have them realign it at that time so if I put more washers in it seems (if what they are saying is true) it would give me more range of adjustment.

Yes ? No ?

 

Yes? No? Possibly? The lower control arm (which the adjustment is normally made in) moves in a slot about 1 inch long. The tech is saying the control arm is all the way to one end of the slot now, and can't go any farther. If the upper control arm was moved the proper direction 1/4 inch, by adding / removing washers, then the lower control arm could also be moved 1/4 inch away from the end of the adjusting slot, thereby allowing some normal adjustment in either direction, of the lower control arm.l

 

Thanks alanh !

So, what you're saying is the lower arm will "follow" the top arm if moved out .