Well today I just noticed something alarming. To me that is. I've had this car (79 C3) for going on 4 years and never noticed this. Recently I posted a thread about raising the rear of my '79 level with the front or maybe an inch higher. I ended up ordering a 'VanSteel' poly bushing 8" bolt kit which should arrive tomorrow. I actually just went out into the garage to put a bunch of PB blaster on the outer spring bolts for when I get to the job. Well, I started looking around the car and I noticed (while looking from the back that my passenger front wheel was sticking out of the wheel well at the top. (Way too much positive camber) Then looking over all the wheels I can see I need a complete alignment and probably associated parts. But here's the kicker- since it needs it obviously is going to need an alignment, I started taking shims out of the right upper "A" frame. I had to take the ALL out on the front of and A frame, and leave one in the rear to keep the same angle. (at least) But then I noticed that the wheel, although still sticking out at the top still, (visually) seems to have negative offset as compared to the passenger front pushing the whole wheel and tired outward!! I can think of two possibilities: 1) There is an incorrect rally wheel on the right front. (Wrong offset), 2) the car was in an accident and put back together with this problem. HOWEVER.... I have taken all of the shims out of the right side wheel and the tire is still tilted away from the car (visually) so I have no more adjustment. I've been working on cars all of my life but have never been and exhaust guy or a front end guy. (Only minor front end parts, and one Rough Country 4" lift kit in my OBS Silverado. Any ideas on what the hell is going on here? ALSO, the passenger rear wheels are tilted in on the top, the passenger side being much more obvious. This is why I didn't want to go for a new rear spring at 1000 bucks because it's something every day with these C3s. I looked over the whole front of the car and I don't see evidence of a serious accident which I think it would have to have been to tweak the frame and the A frames, if they are. I guess it's possible also that because of the assembly tolerances 53 years ago these anomalies are 'within spec?'.

 

When a change is made adding or removing shims, make sure all bolts/nuts are tight..then drive the car around the block a couple times to get the wheel to "settle-in".
Then see if the wheel looks "better".

I bought an aluminum 2' long level with horizontal and vertical bubbles. Then I measured the diameter of the rim and cut equal amounts off each end of the aluminum level so that the level would rest against the rim edges without contacting the tire sidewall.
I held the modified level vertically against the rim and notice how far from center the bubble was. I added or removed shims...drove the car around the block...rechecked the vertical bubble reading. It took me about 3 cycles to get the bubble centered vertically.
I did the same to the other 3 wheels to get the camber centered on all the wheels.
The wheels were now close enough to 0.0 Camber that I could drive the car to an alignment shop and let them fine tune the alignment.

 

Nah...You need the right tool--see enclosed.. this way you can preserve your level for more important stuff like hanging the wife's pictures straight.... a piece of scrap one/by is all you need really,,,

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In the front. As you ADD shims the top of the tire will move in. As you add shims to the rear stud the castor will increase.
reading your comments leads me to believe you have absolutely no idea what your doing.
I suggest you take your car to a professional alignment shop.

 

Perhaps this car's overdue for a really good pro alignment; at the hands of a frame shop. It's quite possible the frame has become compromised; but in a manner that's not obvious. Suggest begin at frame shop and establish a baseline. If frame needs coercing-tweaking; so be it.

 

Ha, ha, that's how I do mine too at home.The alignment shop moto: "set the toe and let it go".

 

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The front end is too high. Too high creates positive camber. Either the coil springs are too tall or they're misaligned in the upper spring pocket. Lowering the front (i.e. shorter coil springs or cutting the current springs) will get you the negative camber you're looking for.

 

Ride height is very important. The first thing that I would do is find out factory ride height. If you are low, or high you may never get the correct camber spec. I don't claim to be an expert, but I have spent hundreds of hours working on asphalt oval track cars. As the car goes through the suspension travel you will gain, or loose camber. Once you make an adjustment drive the car around the block (a few bumps will help) and recheck the camber, that will "set " the suspension. If you notice videos from car assembly plant the cars drive over a series of rumble strips before they check the alignment. Don't give up it can be a long process given you do not have an alignment rig. I like the home-made camber gage!

 

This is why you shouldn’t listen to computer algorithms to tell you how to work on your car.



Think about it, adding shims moves the upper control arm inward. This increases the angle of the spindle between the ball joints, giving you negative camber.

 

I concur. When I took them (an equal amount) of shims out of the upper control arm, I could see space between the frame mounts and the upper "A frame". I then just pushed the wheel up against the A frame with my knee and the top of the tire moved in toward the center of the car. I then tightened the two bolts sans the shims. (I left one in so as not to change the caster) (to get closer to spec for the alignment shop trip). "Race Master" may have his own way of doing things I guess. Or maybe he's a bot?

 

Probably definitely a bot. If it’s good enough to drive to an alignment shop they should be able to get you sorted out there.

The factory alignment specs on C3s leave a lot to be desired since they’re were designed around bias ply tires. With radials you’ll want to get as much caster as possible. Tell the alignment shop you want it set up to the specs outlined here. You can choose between cruiser or advanced street for however you plan on driving.

 

The next time you correct me. Please consider your source of information.
From the genuine G.M. Factory Service Manual.

 

You need to know that not all control arms mount behind the solid mount of the chassis. You reached out for advise , I gave some. How did you reply to the guy who insinuated that you did not know what you are doing? Is this facebook, or the Corvette forum?

 

Well I installed new rear spring bushings finally. I bought the 8" VanSteel poly kit but ended up using the stock 6.5" bolts and adding one large washer on each side on the bottom (from the VanSteel kit) and one small washer at the top (Home Depot) and I think it turned out great. In the picture I hadn't replaced the center caps and I left the sway bar disconnected because I thought I might have to go back and do more adjustments. I took it for a test drive and It feels like a totally different car, it handles and tracks so much better. As soon as I took the car off the jack stands I saw that the rear wheels were standing vertically on the ground whereas before they were noticeably angled in on the top (negative camber) and now had the added clearance.

 

I'm totally confused. Wasn't the OP asking about negative camber for the front? Or, did I miss something.

 

I think we missed the same “something”.

I think the take-away is (should be?)…

• Positive front (tire top out, needs ride-height check, shims on UCA to pull it in)
• Negative rear (tire top in, in spec ok; out of spec adjust strut rod eccentrics / turn-buckles if modified, to pull the tire bottom IN aka top OUT)

SLA suspensions can be the hardest thing to explain to those who don’t do it frequently - and it’s been 8+ years since I had to do one.

I swear I had the hardest time explaining to an apprentice that “subtracting shims in the front and adding shims in the rear results in (hopefully the same) caster but a positive change in camber” …had to get out a cardboard triangle and explain geometry.

Camber & Caster aligning is a pain without tools / machine. We can all do toe - nobody’s arguing about that.

edit: got myself confused with my own explanation :-/

 

I found this on the web and reformatted it; I find it very useful as a guide when confusion sets in.

 

I’d have to say the worst part about alignments is:

Toe wears tires
Camber wears tires
Caster makes steering wheel return

Always set Caster third because you have to set

SIGH

Rear camber first
Rear toe second

Front Caster third
Front Camber third-and-a-half [SLA suspension]
Front Toe last / fourth

If the rear dog-tracks / crab-legs, it will always affect the front.

Only talking alignment angles, not including ride-height which should be first and the rest cascade from that.

If you really want to be a perfectionist, make sure you do these measurements with pre-alignment conditions satisfied [Mercedes is big on these]

• certain level of fuel in the tank
• certain weight in the seats
• certain luggage weight

Alignments become an art at a point.

Never had a customer complain about a steering wheel correction for road-crown (couple of degrees, so it was almost always straight), never let the car leave if it wasn’t right.

@Mickeymoe you’re on the right track, glad you caught the wheel that was wrong. Let us know how it turns out!