myronf

I had my wheel alignment done locally and am not happy with the results.

1. I was charged $340!!
2. I told them what I wanted for specs, but they listened to their machine instead.
3. Even though the whole front end is rebuilt it feels like I am driving on ice with this power steering car. It looks like more caster will make a big difference.

Here is what I've got:

left front
camber -.2 degrees
caster +1 degree
toe 0:

right front
camber -.2 degrees
caster +.9 degrees
toe 0"

Total toe 0

left rear
camber +.2 degrees
toe minus 1/16 in

right rear
camber +.2 degrees
toe plus 1/8 in

They did not touch the rear toe because they were afraid of it.

Looks like I want for the front
0 front camber
2-2/12 degree plus camber
0-minus 1/16" toe

I don't want to go back there, and I don't want to start over. Looking at the manual, I think that adding 5/32" to the front and 1/32" to the back will get me the caster that I am looking for, and get me 0 camber. The book says that "addition of shims to front bolt or removal at the rear bolt will will decrease positive caster. A 1/32" shim will change cater 1/4 degree."

"Adding or removing shims to the front and back bolts will adjust camber. A 1/32" shim will affect camber by 1/6 degree."

Can someone tell me if I did my math right?

In regards the rear, I am waiting till I redo the trailing arms this winter.

856666

PM Sent

DansYellow66

Man - that sucks. Hope they held a gun to your head when they forced you to write that check.

I'm a fan of doing my own home alignments on my old cars for pretty much this reason. A moderate priced caster/camber gage and an inepsensive toe-in tram are about all it takes. I've home aligned my Corvette, Ply GTX and Cobra and all of them will track down a straight road in a straight line with hands off the wheel better than our daily drivers. I bought my 2003 Ford Lightning new and because of the wide tires it tracks terrible, even worse than I expected. I got my gages out and checked it and it appeared out of specs. I took it back to the dealer with probably less than 1000 miles on it and voiced concern - but half expected them to laugh and throw me out when I told them I had checked it in my garage. But - they put it on the rack and came back a few minutes later and said - Buddy, you're right, it's way off - we are even going to have to install a camber kit in it to get it in specs. However, with 295 tires and the SVT suspension it still tracks a straight road like crap.

As to your problem, yes the information on shim changes in the manual is reasonably accurate but your caster is way low (IMO) and that complicates things. I would not hesitate to go up to 3 to 3-1/2 degrees pos caster, especially if you have manual steering. I would have to look up the specs but the .2 deg negative camber up front is probably OK for street. I know 0 deg camber is often quoted as desirable with radials. When you start having to shuffle quite a few shims around at the front and rear bolts, those go-by figures start falling apart. You really need to either decide to get some gages to check what you are doing or find a reliable shop that knows old cars.

You could add a shim or two at the rear to increase your positve caster but that will at the same time result in more negative camber. A better approach is to subtract a specific thickness shim from the front and add it to the rear. In theory that maintains camber but increases caster. But, as I said theory kind of gets lost in some of the variables when you start shifting shims around. And then there will be some change in the toe-in from this. I would have to study it a bit but off hand I believe increasing caster with a rearward tie rod system induces more toe in - but pulling a shim out of the front and adding it to the rear - not sure where it goes then, possibly too much toe in. A solid 1/16 inch toe in is a good setting but you can go up to 1/8 inch. And from here it gets even a little more complicated as ideally you want an addition 1/4 to 1/2 deg + caster on the right side to help compensate for road crown.

On the rear, you need to get rid of the positive camber and get it to 0 deg to a 1/4 deg negative. The rear needs some slight toe in also - up to 1/8 inch. But also the rear needs to be checked to make sure it's in line with the front which usually for me involves a bunch of string lines, straight edges and measuring that would do Rube Goldberg proud.

Think I would ask for a refund and look for another shop. Good luck.

myronf

Thanks for the above responses. Seems like my front caster and rear toe are my biggest problems.

Plasticman

Agree with Dan, including asking for a refund.

And your front toe is not helping either. You don't want "0" front toe for the street......

I also do all my own alignments, and agree that some shops just have lazy or inept techs (and never get an alignment just before closing time).

Plasticman

128racecar

Great advice above. Having done home alignments for 20 years on my race cars, I would add the following bits of advice:
1. Get a level, and find a level spot in the garage or driveway to do the work.
2. Make SMALL changes each time.
3. Allow lots of time (like a whole morning or afternoon).
It isn't hard, but it can be very tedious. It is also very satisfying when your car is set up right.
Marc in Indy

AZDoug

Fastrax alignment machine and two per side 1/8" thick by 12" by 12" aluminum (or steel) plates with grease between them to allow the front wheels to turn easy.

To be fully accurate, put a 1/4" thick something under the rear wheels to keep teh car at stance.

Doug

Plasticman

Doug,

I use 2 sheets of wax paper, with grease between the 2 sheets (so no need to raise the rear) for each front tire.

I am "frugal"........

Plasticman

AZDoug

Good idea, that would work well on a relatively smooth surface, maybe not so much on say, asphalt.

Thanks,
Doug

DansYellow66

I didn't want to get too deep into the how's of home alignments but since some very good tips are being thrown out I will also add a couple:

1. Agree on finding a level spot in your garage floor. At least get the area the front tires are resting on level even it the back tires are a hair off from the front tires.

2. Turn plates are nice but I found a set of wheel dollies also work really well. With this crank up pair I can also use them to some degree to level the car up.



3. I run all of my gage checks at least twice, and maybe three times just to make sure I'm getting consistant readings.

4. The camber/caster gage I use calls for turning the wheel 20 deg out and zero out the bubble. Then turn the wheel 20 deg in and take a reading for the overall difference in the bubble. Find a way to gage the 20 degrees, or whatever the instrument instructions say so that you are consistent and can repeat this. I don't think it overall makes a lot of difference if you end up measuring over 19, 20 or 21 degrees, as long as it's the same both in and out and consistent.

5. Get the toe in and camber as close as you can to what you want. Be sure you have enough caster - but don't get too hung up on getting to an exact caster number. Except in maybe competition driving, the difference between 3 and 4 degrees caster isn't something you will feel. But they do advise to try to get a 1/4 degree or so more caster in the pass side due to road crown.

6. The rear track width on the Corvette is supposed to be .8 inch wider than the front. To check rear suspension tracking I carefully centered the front wheels straight ahead checking against the side of the body with a long straight edge laid on the sidewall. I stretched a fishing line from KO spinner to knock off spinner, used some geometry to figure how much divergence I should get (due to the track width difference) with a straight edge laid lengthwise on the sidewalls to the fishing line at a given distance, and then added to that my figure for toe in. With the rear camber in spec I wiggled in the shim packs on the trailing arms until I was on my divergence figures, again checking with the straightedge. Then with a toe tram I checked the overall toe in at the rear to make sure it was in spec.

I said it would do Rube Goldberg proud.

Plasticman

Agreed.

My concrete garage floor is epoxy coated.

Plasticman

buns

An inexpensive tool is available at Speedway Motors:

6T7L71CPE

I just thought, if this even more simplified device can do the job, why not use an iPhone level?
A little GOOGLE.... there's lots of discussion and at least one app.

http://www.ffcars.com/forums/17-fact...er-camber.html

https://itunes.apple.com/us/app/ialign/id334573404?mt=8