Suspension set up

[z28rob18]

So I finally got a chance to set the suspension up on the car. The toe is 1/16" out camber is within .5* of 0 but my caster is showing about -6*. I don't have adjustable uppers and if I move the lowers it'll move the wheel and get it into the fender. Can factory uppers be adjusted? I also had it on the scales have 47% weight on the rear and its within 35lbs left to right. Pinion angle is 3.5* car weighs 3371! Besides the caster does everything sound good?

[Injuneer]

The adjustment is only on the bottom A-arm. You should be able to achieve factory specs with the range of movement available. The dealer does it with a turnbuckle adjusting tool that connects between the K-member and the A-arm. There is one hole in the K-member for adjusting camber, and another for adjusting caster. With both lower mounting bolts loose, it's just a matter of turning the turnbuckle in the correct direction. It's GM (Kent Moore) tool #J 38658. You can buy them on ebay. See factory manual section 3A.

http://www.ebay.com/itm/KENT-MOORE-J-38658-Caster-Camber-Adjuster-Tool-F-Car-Camaro-Firebird-/161275495083

That's not to say you have to have the tool. I watched a local shop set mine up to my specs without it.

If you have aftermarket tubular A-arms, that's a whole different story.

[z28rob18]

Tubular k member and a arms. I can get it there but think I'll run into issues.

[z28rob18]

Went back and messed with it some more idk why but the gauge I was using isn't reading right. I changed the lower to where I clearly had positive caster and checked it and it showed I had more negative so I set it back and checked with the digital level method and I have 6.1 positive on RF and 5.9 on LF camber is about .1 degree negative on both sides. What about the weight? I feel like it's heavy for everything I've deleted. No AC cruise or abs speed inc carpet with no sound detening material no back seat no sub woofer kirkey front seat pa chromoly kmember and some more. It has a 10pt cage and 9" rear but the weight was without me in it. That's another 190lbs

[Injuneer]

Toe-in, I'd go 0 to 0.1 toed in. That way, under light load, the wheels are more likely to be parallel to each other, and straight ahead, eliminating any tire scrub.

I've kept decent records on what I've taken out (I don't know the details of your car, but I suspect it's fairly drastic beyond big items you have listed) and what I've put back in, and the suspension components, roll bar (I only have a 6-pt cross-braced chrome moly), trans, Gear Vendors, 12-bolt, all braided fuel and nitrous, etc almost balance what I took out. I think last time I weighed it at E town it was close to 3,700 with me (190 #) in it. Still have stock K-member/A-arms.

Pinion angle may be high. With a Spohn adjustable torque arm, chassis mounted, rod end, Steve Spohn set mine to 1.8-deg. I think he reduced the angle based on switching from a poly front bushing to the rod end. With the poly bushing he had recommended 4-deg for track only, resetting to 2-deg for the street. The only reason he set it up himself was because he used my car for the prototype install of his 1-5/16" solid chrome moly race rear sway bar. Since he was under the car, he adjusted the side-to-side chassis height bias for the sway bar, and installed a new torque arm he had built to clear the Gear Vendors unit, and move the DS loop back about 8" from where it is normally located.

[z28rob18]

Last thing with the tubular kmember and adjustable lowers and factory steering do I need to worry about checking bump steer? There isn't really a way to adjust it with the factory tie rods anyway besides length

[Injuneer]

There are bump steer adapters. But this is one area I can't comment on. BMR has a good explanation of the theory on their manual steering rack writeup. Apparently, a significantly narrow steering rack causes the problems.

http://www.bmrsuspension.com/?page=products&productid=266&superpro=0

This is what George Baxter's low 8-second 30th SS convertible had. That is based on a PA tubular K-member. I don't remember what he used for a manual rack.

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