88irocz28

How much camber should the front wheels on an IROC run? The front wheels on my IROC were all out of whack. One was stuffed inside the fender while the other was sticking way out. I thought I had a collapsed strut tower but then i noticed that the struts themselves were out of adjustment. The cover plate on one even had marks indicating that it had worked loose and out of adjustment. I adjusted both front wheels so that they are now running just a hint of neg camber. The feels totally different now. the steering is effortless compared to before and i can actually make right turns without fighting for control. The car would even budge from a stop with the wheels turned right. Now it's a lot better. The front wheels have also worn out like a bitch on the outside edge. I hope what i did was right. Any comments?

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'88 IROC 305 TPI
Gutted airboxes
160 degree T-stat
Advanced base TPS voltage
Relocated IAT sensor
Momo steering wheel
Ram-air setup coming soon

Stuart Moss

'88,

My 1991 Camaro service manual shows a camber of 0.30° (+/- 0.50°). I had seen a post or tech article that suggested running 0.0° or slightly negative camber, depending upon your style of driving. I guess the more aggressive, the more negative from stock.

Anyway, I have mine adjusted for + 0.0° (still within factory specifications - see above).

I have about 10K miles on Yokamaha AVS S4/z (245-50-16), and noticed a lot of wear on just the outer edges of both front tires, about 1/8" less tread than on the inner edges. The outer 1.5" of both tires have a lot more wear than the rest of the tread (the inside tread of both front tires had were like the rear - very little wear). My camber was w/i specifications.

I found out from several sources (including TireRack, where I purchased the tires), that this is common from aggressive driving (who, me?), and especially so for the Yokahama tires. (Rear tires had practically no wear).

If you align your front-end yourself, I wonder how you determine caster? I align my front-end myself (toe and camber), but I haven't figured out how to determine the caster angle unless I purchase a $200-250 tool.

I guess that type of wear will clue you in to the driving habits of a previous owner (or be suspicious if it has new tires).

88irocz28

My front tires are showing exactly the same signs as yours. The outer edges of the tread are disappearing like tires are made out pencil eraser rubber. The rear tires have feathered a little bit thanks to hopping on the gas at stoplights. I don't make hard and fast turns either so it has to be bad front end alignment. The factory settings are often not optimal so it might make sense to dial in more negative camber than the factory suggests. I didn't use any tools to determine the camber - I was fixing another problem and the change in camber was only a side effect. The driver's side strut had somehow gotten knocked all the way in towards the engine and car was leaning to one side, dragging the tire, especially through right turns. Since my tires run flush with the edges of the fenders, I used the rear tires as a reference point when adjusting the front ones. i still have to go to an alignment shop and get it properly adjusted, but the car is still a lot easier to drive than before

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'88 IROC 305 TPI
Gutted airboxes
160 degree T-stat
Advanced base TPS voltage
Relocated IAT sensor
Momo steering wheel
Ram-air setup coming soon
Flowmaster muffler

BretD 88GTA

With the factory camber setting my GTA would wear the outside edges of the front tires.

I'm currently running -0.5 degrees of camber. Tire wear is now more even.

I have heard that GM actually puts a little positive camber into their cars. This means that at 0 degrees you are still seeing some positive camber and that's why our tires wear the on the outside edge. I haven't confirmed this but it seems to be true.

88irocz28

Yeah I wouldn't be surprised if GM has been putting positive camber on their vehicles. Everybody seems to be getting the same kind of wear on their tires here. While the whole sports car world dials in negative camber for better cornering (even the Corolla comes with negative camber from the factory) GM's going the opposite way.

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'88 IROC 305 TPI
Gutted airboxes
160 degree T-stat
Advanced base TPS voltage
Relocated IAT sensor
Momo steering wheel
Ram-air setup coming soon
Flowmaster muffler