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Discussion Starter #1
I have a 3rd gen camaro with the racecraft stilletto front susp. kit. ran for the first time last weekend and about 75-80 mph the car starts to death wobble like crazy. some buddies in the stand were freaking out thinking my front tires were coming off.

Guess i am looking for some advise on where we should start. everything is tight.

i have 3 u-joints in my steering shaft, i only have one brace between the first two u- joints, should i add another between the other two?

tires are 26x4.5x15 running at about 40 psi
toe is at at about 1.5* if i remember right ( i will check my spec sheet when i get home)

any other ideas on what could be causing it?
 

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toe should be zero with the front up about 1.5-2 inches from the resting position, I like 5.5 to 6 degrees positive caster, 0 camber. Be sure the suspension components are all tight and not worn, make sure the tires have no flat spots from sitting, I would run no more than 30-32 psi in them too, lets them get wider (more foot print) when your on the brakes. I have had the wobble but only when coming down from the wheelie, used a steering dampner from ed quay to solve that but thats with the stock steering linkage. Have you had it on a alignment rack?
 

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Discussion Starter #3
Yeah we have had it on a rack, all the parts are brand new and this was the time out. called Mark at racecraft and he said to try some more toe in the front end to try and preload the tires. i am adding another rod end on the steering shaft as a brace. tires are also new, after the first pass we went over every nut and bolt and everything was tight. totally lost on where to go
 

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toe should be zero with the front up about 1.5-2 inches from the resting position, I like 5.5 to 6 degrees positive caster, 0 camber. Be sure the suspension components are all tight and not worn, make sure the tires have no flat spots from sitting, I would run no more than 30-32 psi in them too, lets them get wider (more foot print) when your on the brakes. I have had the wobble but only when coming down from the wheelie, used a steering dampner from ed quay to solve that but thats with the stock steering linkage. Have you had it on a alignment rack?

I like a little negative toe. If you have a 1.5 positive toe that thing will bump steer all over the track. Your positive toe will increase as you go down the track. Flat spots also as stated above. Check the tires on a balancer. Spin them and look for out of round.
 

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I like a little negative toe. If you have a 1.5 positive toe that thing will bump steer all over the track. Your positive toe will increase as you go down the track. Flat spots also as stated above. Check the tires on a balancer. Spin them and look for out of round.
Rule #1 for a drag car alignment: never, ever, ever set the toe negative. That is asking for a crash.
 

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i had the same issue and it turned out to be negative toe.

I set it straight, fixed the bumpsteer, and no more problems.

does the car steer straight and easy at low speed,
 

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Discussion Starter #10 (Edited)
the toe is setup neg. 1.5* right now, i was told i HAD to have some amount of toe by the guys at Racecraft. We put as much positive caster in the car as possible. (wheel forward of the strut mount point, strut leaning towards rear of car) i am pretty sure it was somewhere in th 5-6* range.
 

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Negative toe will make the car a handful at speed. Never seen it cause wobble, but I suppose it could. Verify the caster is positive and even side to side and camber is 0, and set the toe POSITIVE. 1/8" - 3/16" should be fine. You can set it yourself with a tape measure.
 

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Negative toe will make the car a handful at speed. Never seen it cause wobble, but I suppose it could. Verify the caster is positive and even side to side and camber is 0, and set the toe POSITIVE. 1/8" - 3/16" should be fine. You can set it yourself with a tape measure.
Whar are you calling positive toe?
 

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Discussion Starter #15
So update: car still has the same problem, same setup, had it on the rack several times. Caster set at 6*, 0* camber and have tried everything from 0* toe in to 2'' of toe in and still no luck. now on the rack with the steering locked i can grab the tire and get 1* of toe just by shaking the tire back and forth. I am going to try a completly different set of wheels and tires and see what happens. just seeing if there was any other ideas from anyone?
 

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So update: car still has the same problem, same setup, had it on the rack several times. Caster set at 6*, 0* camber and have tried everything from 0* toe in to 2'' of toe in and still no luck. now on the rack with the steering locked i can grab the tire and get 1* of toe just by shaking the tire back and forth. I am going to try a completly different set of wheels and tires and see what happens. just seeing if there was any other ideas from anyone?
Find out why you have 1" of toe change. Try this..... With the vehicle on the alignment rack, push out on the front of both front tires from under the vehicle simultaneously. If there is more than a 1/8" toe change, then find out why. If there isn't, then monitor the toe reading while pulling or pushing on the left and right side wheels individually. Once again there should be no more than an 1/8" change. And I do mean at the most.

One other thought.. Is the steering rack mounted in rubber? If so then how tight are the rubber mounts/bushings to the rack body?
It's critical....

Thanks,
Larry S.


http://www.precisionautomotivespecialists.com
 

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So update: car still has the same problem, same setup, had it on the rack several times. Caster set at 6*, 0* camber and have tried everything from 0* toe in to 2'' of toe in and still no luck. now on the rack with the steering locked i can grab the tire and get 1* of toe just by shaking the tire back and forth. I am going to try a completly different set of wheels and tires and see what happens. just seeing if there was any other ideas from anyone?

http://shop.edquay.com//product_info.php?products_id=504&osCsid=7ab5b41d3408f15d9fa52db8c1aedcd9
 

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bump steer,my 3rd gen we had lowered the car and custom k member. In the end it went to chassis shop and had to get the control arms lenghtened and the struts relocated.
 

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Anyone have some pics of the damper installed?
 

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I had the same issue and it is a common problem on these cars . Have heard alot of different ideas on why and never had luck with any of them . Put a rack on the car and the problem was gone !! Personally I think that the multiple joints and the front end geometery is just wrong for drag racing .

Does this look familiar http://www.youtube.com/watch?v=JIsr_VfzP6k&list=UUXOPjJ_qy6x-d3WTBKUrP4w&index=1&feature=plcp

Do yourself a favor and convert to a rack before you end up with something bad happening JMOP !!
 
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