How does raising/lowering a C5 affect camber.
Thread Starter
Racer
Joined: Dec 1999
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From: Dallas,TX,USA
How does raising/lowering a C5 affect camber?
I was noticing on my old slicks(26x 11.5x 16 ET Streets), that one side of the tire has greater wear than the other. Actually, it is a 3 inch wide section of the tire 2 inches from the inside that is corded while the rest of the tire has some tread left. The rear end was raised to see if it would help with the launch. Are the tires to wide? Did raising the rear end make the camber positive? When you launch, does your rear tire camber go positive or negative? Trying to decide on what type of tire set-up to run.
[Modified by RunNE1, 11:10 PM 12/15/2003]
[Modified by RunNE1, 11:10 PM 12/15/2003]
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From: Defending the US Constitution in Northern CA
Re: How does raising/lowering a C5 affect camber? (LT1LS1)
:yesnod:
As the rear of the car squats durring launch, the camber goes more negative (leaning in at the top). For drag racing, set your rear Camber to a range of zero to + 1/8 degree for a good flat foot print upon launch. this setting will be acceptable for street driving as well, but would really suck around corners. Try dialing in a bit of toe out in the rear as well, as the rear tires trie to toe in durring hard acceleration.
As the rear of the car squats durring launch, the camber goes more negative (leaning in at the top). For drag racing, set your rear Camber to a range of zero to + 1/8 degree for a good flat foot print upon launch. this setting will be acceptable for street driving as well, but would really suck around corners. Try dialing in a bit of toe out in the rear as well, as the rear tires trie to toe in durring hard acceleration.
Race Director
Joined: Sep 1999
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From: CONCORD NC
Re: How does raising/lowering a C5 affect camber? (C5stein)
You really need to measure both static camber and toe, AS WELL AS bump steer. If you haven't actually measured what you have, it is hard to suggest a course of action.
Excessive toe can really cause wear as you describe, but we need more info!
Excessive toe can really cause wear as you describe, but we need more info!
Thread Starter
Racer
Joined: Dec 1999
Posts: 442
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From: Dallas,TX,USA
Re: How does raising/lowering a C5 affect camber? (davidfarmer)
Thanks for the replies everyone, I figured that the camber went negative, but wasn't sure. I wonder if going to 10.5's would spread the load more evenly over the tire?
David, the only modification I have done, is to use shorter bolts to raise the car up more. I am not sure how this affects the camber and toe-in/out from the factory specs. I really would not know how to go about measuring for camber, and toe-in. Is this something only an alignment shop would be able to measure?
Thanks
David, the only modification I have done, is to use shorter bolts to raise the car up more. I am not sure how this affects the camber and toe-in/out from the factory specs. I really would not know how to go about measuring for camber, and toe-in. Is this something only an alignment shop would be able to measure?
Thanks
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From: CONCORD NC
Re: How does raising/lowering a C5 affect camber? (RunNE1)
you can do it. Just take a level, a tape measure, and a straight edge. You should be able to get an idea.
btw, to find camber ange, use the level. Measure the amount (x) the top sits in or out, compared to the bottom. "d" is the diameter of the tire at the point you make your measurement.
then, tan (angle)=x/d or, Angle= inv-tan (x/d)
If you aren't good with geometry, just use windows calculator. Divid your X by D, then click the little "Inv" button, then hit "tan". Make sure the "Degrees" box is checked not "Radians".
Toe is a 2 man job, for most. Each person needs a straight edge. Hold your edge against the front of the measured tire, on both sides. I usually measure it with the straight edge against the tires (flush top and bottom) at the edge of the bead. Slide the tape under, and measure the distance where the 2 edges touch the ground. Do this at the front of the tire, and at the rear of the tire. The difference in the two numbers is to (in or out).
It takes practice, but you should be able to get consistent, repeatable numbers, with a little practice.
Dave
btw, to find camber ange, use the level. Measure the amount (x) the top sits in or out, compared to the bottom. "d" is the diameter of the tire at the point you make your measurement.
then, tan (angle)=x/d or, Angle= inv-tan (x/d)
If you aren't good with geometry, just use windows calculator. Divid your X by D, then click the little "Inv" button, then hit "tan". Make sure the "Degrees" box is checked not "Radians".
Toe is a 2 man job, for most. Each person needs a straight edge. Hold your edge against the front of the measured tire, on both sides. I usually measure it with the straight edge against the tires (flush top and bottom) at the edge of the bead. Slide the tape under, and measure the distance where the 2 edges touch the ground. Do this at the front of the tire, and at the rear of the tire. The difference in the two numbers is to (in or out).
It takes practice, but you should be able to get consistent, repeatable numbers, with a little practice.
Dave
