KITT87

Hey all, I’ve read a few threads on this but wanted to see if I could get some specs closer to my situation. A few months ago, I replaced the front steering linkage and got the car aligned afterwards. I wish I had read a bit further into forums because just as you guys said, the factory specs for an alignment are trash. The outside part of driver’s tire wore out in less than 4 months. I’ve got two new tires on it now and I’m two alignments in from the GM dealer and it still feels like it did before the tire change (bad).

Does anyone have any recommendations for what alignment specs to run? Car is a 1987 Firebird with the base suspension, sitting on the factory 15s with 245/60 tires. I drive the car daily and live in southwest VA, so the crown of the road is pretty decent. I’ve attached the alignment sheet from last time down below.

I’m aware that a worn steering box and/or worm gear can also cause some of the problems (uneven tire wear, wandering) I’ve been experiencing. I’m trying to rule out bad alignment specs first since it’s under warranty. Apologies if anything I said is dumb or wrong, I’ve always got more to learn about these cars

SilverChicken

iTrader: (1)

I would personally run more caster if possible (you might be maxed out on the right side) but of all your specs the only thing that was an issue before the alignment was your toe. Now your alignment tech has adjusted your car to have positive camber. Thats always a problem. A half degree of negative camber is perfectly acceptable on a daily driven car and preferable for handling and tire wear.

KITT87

Gotcha, I’ll mention it when I talk to them on Wednesday. Thanks!!

clubber

iTrader: (1)

Yep, positive camber will reduce front end stick and wear out the outside edge of the tires especially if you like to corner enthusiastically. A little less front toe will help steering response and help tire wear as well.

clubber

iTrader: (1)

I just looked again at your alignment specs and noticed that I messed up on the toe comment. I was looking at the "pre" spec for my comment on it. They setup your toe fine, It needed adjusting before and what they put into your car is about perfect. What I said about the camber was right. Positive camber is a bad thing on these cars and almost all other cars too.

KITT87

Thanks for clarifying. And thanks to both of you guys for the quick and helpful responses. I’ll check back in after I get the alignment done

C.fox

Thank you for sharing this.

You saved me some time.

McLovin1181

OEM alignments are bad because people were complaining back in the '80s.
lots of steering lock and slow speeds makes the front suspension feels odd.
So GM changed specs to a horrible toe out + positive camber with very little castor
My recommendation.

Daily:
-0.5 camber
+5 caster
0.2 degrees toe in.

Hard street:
-1.0 camber.
+6 caster.
0.1 deg or zero toe.

Hard street + some racing:
-1.5 camber
+6 castor
0.1 degree or zero toe.


All out ***** to the wall racing.
-3.5 camber or more.
+6 castor or more.
High speed tracks: Zero toe.
Short tracks or autocross: 0.1 or 0.2 deg toe Out.

Note: Different suspension setups and tires will change the required camber settings.
For example: A race tire with soft side walls will need more negative camber than a tire with stiff side walls.

Eightyninef

Very simple. Slam the strut towers all the way in & back. Then set the toe with a string and done.

KITT87

Attached below are my final alignment specs. Sorry the sheet looks like garbage, it got rained on. In my admittedly limited observation time, it seems the front tires are wearing evenly.

It is still wandering a bit. I’m aware that the specs aren’t dead on for what was recommended, but at this point I’m pretty confident it is some of the other wear items I have not replaced yet. It does feel a lot better than what it was before. Thanks for all the responses!!