here's my alignment chart after replacing struts, springs, a-arm bushings, and founders strut mounts.

they said the left side physically woudlnt move any more for the caster. oddly enough, the spec on the caster is different from left and right. i also notice the top of the sheet says 'pontiac firebird 87-92 (modified specification)... i wonder if they modified the spec so they woudln't have to get it perfect?

_______LEFT:__RIGHT:__RANGE:
Camber: 0.7___0.2____-0.2 - +0.8
Caster:__6.2___4.9____L(5.7-6.7), R(4.4-5.4)
Toe:___-0.03__-0.03___-0.10 - +0.10

cross camber: 0.5_____-0.7 - +0.7
cross caster: 1.3______ 0.6 - 2.0
total toe: -0.06_______-0.20 - +0.20

 

I hate it when cars are set up with split settings like that, most of the US cars I bought had it like that and I suspect its done to counteract crowning of the road (for water run off?) very annoying in that if you are on a level road like they have here the damned thing is always pulling or pulls easily with soe uneveness. I would have both sides set up the same, so set both to about 4.5 caster, half a degree of camber and the toe looks ok.

 

Positive camber is bad. Negative camber is good. Those look sorta like the GM specs. There's tons of posts on here regarding performance alignment. Get about -0.5 degrees camber on both sides atleast for performance handling. I run -1* and drive it on the street.

 

in regards to the left camber... thats what i'm talking about. he said he couldn't get it any closer, but its still 'in spec'. so i'm wondering if he modified the spec, cuz i dont remember ever having a split spec.

hellz, why is positive caster bad? this is a street car... i'm more concerned about proper tire wear than handling.

 

Positive CAMBER is bad; that means the top of the tires is farther apart than the bottom. The car is "bow legged". It needs to be "knock kneed", with the tops of the tires slightly CLOSER TOGETHER than the bottom.

Caster is the angle of the imaginary axis that the tires turns around when steered. If you have positive caster, the act of steering the car, LIFTS it; meaning any motion of the wheel away from center, adds to the "centering" effect. Too much though, makes it REAL sensitive to roads that aren't level from side to side.

For typical AMerican roads with high center crowns for drainage, good settings are about 4 - 4½° positive caster, with about ½ - 1° more on the left than the right (depending on how the roads are built where you live); about 1° negative camber on the left and ½° negatiove on the right, again, the split depending on how crowned your roads are; and about .03 - .05" of total toe IN (tires steered toward each other slightly.

This will give most people's idea of the best compromise of handling, ease of driving, and tire wear.

The GM specs SUCK. I can't imagine what possessed some IDIOT to publish specs for POSITIVE camber on these cars. That's just BALD-FACED STOOOOOPID. The ignorant engineering intern or co-op who did that for his sophomore project should spend the rest of his eternity in Hell buying people tires.

 

I said positive camber was bad, not caster. Camber is adjusted by moving the strut mount either inwards towards the engine (for more negative camber) or outwards away from the engine (for more positive camber). Positive camber or negative affect handling in different ways, and wear out the tires in different ways too.. Negative camber will wear out the insides faster and positive camber will wear out the outside faster, but negative camber is better for handling so why not set them to negative? My car handles much better and more stable like this as do most any sports or performance oriented car.

 

If that is all you care about and as long as it drives straight then just leave it where it is.

 

I can't stand bad alignments. Too many people end up saddled with them. I'm afraid you stand to get a much better setup than you have.

Camber: You have +0.7 and +0.2.........This guarantees that your front left tire will be bald on the outside edge in no time at all. And you're leaving a lot of handling on the table with these specs. Have them re-do it and set the camber first. Aim for a minimum of -0.5 for both sides. -0.8 would be better. Setting it at -1.0 would be considered a very aggressive setup. With this you "might" get inner tire wear if you do a lot of highway driving. But it will make the car a lot more fun to drive. Personally I've never had a problem with inner tire wear on any car I've had.

Caster: You have 6.2 and 4.9.........Again, this is the reverse of what you want. You should ideally have these either the same or else preferably about 0.5 more on the RIGHT side. The trick is that after you've had the camber set, you should then set the caster to max out the right hand side. And then set the left side aprox 0.5 less than the right.

Toe in is pretty good.

I seriously question the specified range for the left caster at 5.7-6.7.......The factory spec for my 89 is 4.7 on both sides for caster.

Use the picture below as a guide for what you want for alignment settings and you'll do well.

 

Wrong numbers for camber?
These numbers seem to be for the drive on the left like Japan and England, where cars tend to pull to the left because the left side of the road is lower than the center.

 

You're right; sorry, should be a slightly higher negative camber and slightly higher postive caster on the RIGHT for American roads.

 

after a major debacle, I finally got the alignment fixed.

they did indeed lie about the specs... i go back a 2nd time to get it fixed, and they now tell me they cant do it because i had a bad idler arm and inner tie rod, and thats probably why it came out bad the 1st time. they were indeed bad... but why didn't they notice it the first time?

i go back a 3rd time, and now they tell me they cant do it because they need a 'special tool' which of course they don't have. (the tool is like a turnbuckle that holds the strut mount in place while they tighten it down)

i get sick of them, and decide to go to a different location, 10mi away for my 4th attempt. this guy gets it right, WITHOUT any 'special tools', and he even was willing to try to accommodate those suggested specs. it visually looks a little ugly, as it had the inside part of the mount pushed all the way to one side because he said the mount itself wasnt centered (why didn't he move the mount before starting??), but as long as its a decent result, i'll take ugly at this point.

i think i left my sheet on the desk at the shop, but from memory, here's my results:
he HAD the camber at a perfect -0.5 on both sides, but it moved a little after he redid the caster a 2nd time.

_______LEFT:__RIGHT:
Camber: -0.8___-0.5
Caster:__4.5____4.7

 

I do not know what is with these shops. I can do this in my garage just as fast if not faster without an alignment rack and I guarantee it is more percise outcome then what they are doing. All it takes is a floor jack and a rubber mallet, and a little bit of knowledge and you do not need any special tool.

I am building a special STB that is adjustable for a good friend so we can make pit stop type camber adjustments at the track without even jacking the car. Ill post pics when we get it finished this month.

 

if i could do it myself, trust me, I would!

 

If you lived near me Id do yours for free - trust me... It doesn;t take long. I've helped many people with several diffetent types of cars.

Actually it would not quite be free, I require two Jack-in-the-box taco's and a large cola slurpee.(Im not joking)

 

hows this alignment I just had done look?
-.5 -.5
+6.5 +7.5
toe in 1/8"

 

Can you scan and show your alignment sheet? Id like to actually see that on paper how they managed to get 7.5* caster

 

the max i could get on my 86 on the right side was 4.8 i think..

 

I didnt get the printout he just gave me his hand written notes. I have adjustable strut mounts on the car.:

 

I can get better than that is my garage with a camber gauge and toe plates.