sothpaw2

I've read up on this and have been adjusting my car's ride height on the stock bolts.

Short question: On the rear, to lower, you turn the bolt CC, making the space between the A-arm and spring longer correct? :o

I'm making small adjustments now so it's hard to be sure...

Thanks

Andy

joeflyer

Correct. Longer bolt length equals lower ride height. This is reverse of the front suspension.

striper

Just undo the rear bolts until there are almost no threads left. Tighten the front bolts until you can't tighten any more. Actually, I would first remove the front bolts and cut the rubber bushings in half and then reinstall and tighten. That's how my car is done.

Solofast

Actually if you do this the way striper recommends your car will handle like a pig, ride rougher than an ox cart and in a few months you will be back at the alignment shop because it is wandering all over the road.

Look in the sticky at how to do it right. If you lower it too much in the back the rear shocks will bottom out and that will not only screw up your handling, it will ruin your alignment. You should expect the rear screws to be different. If you adjust them to be the same the corner weights will be off and the car will oversteer turning left and push turning right. There's a right way to do it and a wrong way, and you will just make more work for yourself if you screw it up.

Here is a link to the right way to do it.

http://forums.corvetteforum.com/1576940245-post106.html

helga203

Sorry. Simplest way to lower, put a 600lbs guy on the top of your car.:craz y:

sothpaw2

That's interesting about the rear bolts being different left vs right. My right side is maybe .125" higher. Even the RF is a little higher than the LF. I'll have to get it on scales some time...what should the 4 corner weights be...equal?

BTW--I did lower the fronts a tiny bit from where the shop had them and now both screws are 1-2 thread from bottomed out. The height as measured on the rail at the front jack point is about 4.875". At least for my 2002 unit, I don't see the front going much lower on unmodified stock bolts.

Solofast

The bolts are't different, the chassis is bent. They all are cause that's the way the tooling was made. When you get the car cornerweighted the rear screws will be different by about two or three turns. It's not a big deal, but if you lower the car so that the bolts are even your corner weights will be off by a good bit.

What you want to do when you are corner weighting the car is get it so that the percentages of weight from front to rear on each side are the same. That is, if you have 52% front and 48% rear on the left side you get the same percentages on the other side. That way the car corners the same going left or right. When doing the corner weighting, simply compare cross weights (sum of LF and RR) to (sum of RF and LR). When they are equal you are properly balanced. Note that the left side will be a little heavier than the right, but that's because of your weight (you should put weight in the seat to simulate the driver) and the weight of other stuff in the car like the steering wheel make the left side heavier.

seoulbrooks

Previous owner just maxed out on the stock bolts. Vette was all over the road and beat me to death. I know its a sports car but ones body can only handle so many bone shakes. When they put it up on the rack the rear shocks were bottomed out and the front had very little play. They adjusted the height back to within OEM specs and did a new alignment. Was I pleasently shocked on the ride home, lt was like I had a new vehicle. Handles much better and ride quality is now comfortable.

sothpaw2

Good info.--I wouldn't have guessed a difference in chassis left to right.
As measured at the jacking points on the frame rails, is 1/8" about the same as 2-3 threads of the bolt????

Solofast

Don't know how much shows up at the jacking points. LG motorsports has had a bunch of C5's on their surface plate and measured them prior to setting them up for the track. They said all of them were pretty much the same and in one thread on the Road Race and autocross page they noted how much it was. They said it was in the kickup on the passenger side.

And OBTW, most of the rear subframes are actually offset to the left of the car about 1/4 of an inch too. To get a proper alignment if you are tracking the car you will need to grind the hole in the frame that the rear subframe pin sticks into by about 1/4 of an inch. Otherwise you end up with about -1 degree of negative camber on passenger side and -2 degrees on the left. If you move the subframe you can get it centered properly and get -1.5 degrees on both sides.

leadfoot4

FWIW, I'll suggest this....With your car on as flat a surface as possible, use the lower a-arm pivot bolts, both front and rear, as your measuring points. Equalize these measurements side to side, with a little front downward rake, for aerodynamic stability.

sothpaw2

Not a bad idea about the A-arm bolts...do you have a pic of them though? I'll have to open her up and also the shop manual. This reminds me though that I could also look up the official way to measure ride height here and at least derive what to measure left & right.

The frame rail at the jacking ponts is really easy to measure from so very convenient. Right now I have :

LF, RF: 4.79", 4.65"
LR, RR: 5.03", 5.06"

I would think since the car is symmetrical in the rear that if you measure from the rails the rear should be fairly even. I'm not super happy about the front but both bolts are about 1 thd from bottoming out. From what I've read, lots of folks set the car up this way (front almost bottom out, rear add some rake).

Jason

Don't forget to add your weight to the driver's seat.