I should kick myself for letting anybody work on my car besides me. I had my front springs changed and front lower control arm bushings changed. Now, the cross-caster difference on the alignment is -1.2 degrees to prevent the car from pulling to the right. I've never had a large difference before. Camber and toe are fine. Any idea what they screwed up on?

Thanks, Dave '91 T/A

 

Could the lower control arm bushing bolts have been tightened with the car in the air? That would induce a "twist" in the bushings, but I don't know for sure if it would throw off alignment specs..? Usually it makes for a stranger ride since the car would be riding "higher" than it should.


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-Tom P (Hot rodded 1986 Firebird 2.8l) from http://www.f-body.net/mailbag/3rd/3rd_mailbag.html message boards
---Think your car could be pic of the week? Visit http://www.f-body.net for details!

 

The bushings may have been tightened in the air, but since they are Del-A-Lum bushings (metal sleeves), I doubt they could be distorted very much.

Thanks, Dave

 

Post your actual specs and I will help you. Been aligning cars for about 6 years.

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84 Camaro ZZ4 with HOT cam. 1.88 60' (12.98 @ 105MPH E.T.)
Other Mods: You name it and I have probably changed it.

91 Firebird 5.0L TBI

ASE Certified Auto Tech
LIVE AND DIE BY THE ALMIGHTY BOWTIE!

 

Upper strut mount bushings? Can't align correctly when they're worn-out!
DC

 

Here are the specs:
Left camber .2 deg., Right camber .5
Left caster 4.6, Right 5.8
Left toe .03, Right 0.0

Here is the reason I believe they screwed something up. My car always had specs that were very nearly identical for right and left front before. Only after the work was done, is there a large pull to the right. So, I doubt the strut mount or anything else suddenly went wrong. I'm guessing that when they put in the new front springs, they didn't line them up the same way or seat them the same. Would that cause the caster to be off?

Thanks, Dave '91 T/A

 

Got a theory for ya. If the old rubber bushing toward the back of the right front lower control arm was crushed (worn out) then the caster would read lower on the right side. Putting in the metal bushings brought the right side control arm forward, increasing caster. The right side is a little higher than the stock upper mount should allow so there might be some body damage or a suspension component bent. Highest stock caster readings should be 5.5 degrees. The car should pull to the side with the least amount of caster, left. So your right pull is confusing to me, unless you have tires with alignment wear. If that is the case then you will never fix the problem until new tires have been purchased. Camber and Toe look GOOD for stock upper mounts. Have an alignment shop put caster on the right side in spec and rotate your front tires to the rear. This should fix your problem for sure. Just make sure the alignment shop gives you a print out with specs that you have specified because when caster is moved so is camber. Another good reason for giving specific specs is so that some amateaur does not "shoot for the green" indicating your car is aligned but not optimized. If you need specs let me know what kind of driving you want to do and I will provide them. BTW if you want to check the springs then measure each fender well from level ground and make sure they are identical.

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84 Camaro ZZ4 with HOT cam. 1.88 60' (12.98 @ 105MPH E.T.)
Other Mods: You name it and I have probably changed it.

91 Firebird 5.0L TBI

ASE Certified Auto Tech
LIVE AND DIE BY THE ALMIGHTY BOWTIE!

 

CamaroMike,
Thanks for all the input. I'll definitely rotate the tires. And I'd like a recommendation for front specs when I get a more neutral handling car. You can check chassis balance issues thread for my mods and current balance problem. I have a setup that I would describe as aggressive street.

Thanks, Dave '91 T/A

 

My Camaro is running
Toe: 0,0 for straight line performance
Toe In is for high speed and Toe Out is for autocross (low speed). At high speed tires will tend to Toe Out so point the tires in (Toe In) and at low speed pointing the tires out will take slop out of the steering. Toe at 0,0 will provide a best of both worlds and help 1/4 mile performace.
Camber: -1,-1 if possible. Thats what I run with my J&M caster/camber plates. More negative Camber will cause excessive wear and reduce 1/4 mile performance. With stock upper mounts run as much equal negative camber as possible. It will usually be around -.25,-.25. Just keep them equal! Caster on my Camaro is at 6 degrees equal on either side for very high speed stability (140+) but it is an arm wrestler with my Z28 fast ratio box. On a stock upper mount I would run 5,5. Actually on your Camaro you could run 5,5.5 to fight road crown (tendancy to drift right because of road slope) but on a flat surface with big tires it might pull left. I would go 5,5 on your car.

So recap-
Toe: 0,0
Camber -.25,-.25
Caster 5,5
All numbers are LEFT,RIGHT and in degrees.


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84 Camaro ZZ4 with HOT cam. 1.88 60' (12.98 @ 105MPH E.T.)
Other Mods: You name it and I have probably changed it.

91 Firebird 5.0L TBI

ASE Certified Auto Tech
LIVE AND DIE BY THE ALMIGHTY BOWTIE!

[This message has been edited by CamaroMike (edited December 20, 2000).]

 

Well, I measured the gap between the tire and fender. The right side is higher by about 1/4". I think this explains why the caster is off. I'll have my speed shop re-adjust the springs, and align my car with your suggestions.

Thanks, Dave '91 T/A

 

>>>Toe: 0,0
>>>Camber -.25,-.25
>>>Caster 5,5
>>>All numbers are LEFT,RIGHT and in degrees.

CamaroMike, just wondering - doesn't your car pull to the right if your caster is set equal on both sides like that? I would have thought the crown in the road would be causing a constant pull.

Hellraiser

 

With one of my front spring not seated, it pulled real had. I stopped right after the car left the driveway and beat it into place with a 6ft solid steel rod. It slammed so hard back into place that I thought I woke the neighbors, didn't help that it was 2am.

If you seriously think the suspension was tighten up with the A-Arms hanging, I strongly suggest that ya loosen the bolts and retorque them to spec with the suspension fully loaded. Don't forget some locktight, DEl-A-LUM tends to rattle bolts loose.

Get the car at ride height with 4 ramps or 2 ramps at front and jackstand under the rear end with the car as level as you can. Either way, all four springs are fully loaded.

If the car is lowered, make sure all sway bar are cut to allow the bar to be level at ride height. Check your front sway bar to see if it is level. It might be higher on one end. Mine almost had to be cut in half for the rear. Not doing this in the front at first on my 89 caused the front mount to crack from the extremely unlevel angle the bar was at. The car handled much better after that.