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69blackwhss
08-20-2011, 07:21 PM
Heys guys,
I don't know if this is the rite place for this r not. If not let me know an I'll try there.. I have a 69 Camaro with 17 inch wheels an when I have it wheel alignment done they use stock numbers! An I wear the front tires out way to fast, the wheels ride on the inside of the tires an I need new tires now an I still have like 60% life left on them!! Does anyone know what numbers to put for the wheel alignment? They guys said if I had numbers to use they would do it but If not then they got to use stock numbers to alignment by! So any help would be great guys am tried of buy front tires befor I need to.
Thanks jason

rustomatic
08-20-2011, 09:40 PM
If you really don't want to try it yourself (took me 10 to 12 times to get it right) with string and a level (better equipment is available), find a guy who can align the old fashioned way, without the stupid computer pods. Better still, find a guy who's been doing it for about 30 years, and is capable of understanding what camber actually looks like on a wheel--this is not a common talent in today's alignment shop. The main point is this: Most guys who align cars for a living suck at it. Learning how to do it yourself is the best relief, and it's really not that hard. Just be patient, and stay away from chain tire shops.

69blackwhss
08-20-2011, 11:57 PM
Thanks but I'll looked around here for a guy like that no luck! Gggrrrrrrr

JHamister
08-21-2011, 04:05 AM
Here's some information that may help.

http://www.pozziracing.com/first_gen_suspension.htm
(http://www.pozziracing.com/first_gen_suspension.htm)

exwestracer
08-21-2011, 04:45 AM
Sorry but 17s aren't that big a stretch on that car. You should still have some sidewall there (although you didn't provide tire size...). Don't see why the stock alignment settings would be THAT far off... Inside wear is usually caused by excessive negative camber or toe out, BUT a lot of caster can cause quick inside edge wear, esp. if you drive on twisty roads most of the time.

SLO_Z28
08-21-2011, 07:39 AM
This car is primarily a street car that sees spirited driving? Ill give you some specs and explain why I chose them.

Camber 1.0-1.25 degrees with "Cross Camber" being a very critical number. You want slightly less camber on the the drivers side, this will compensate for road crown. The amount of difference is determined by the cars suspension type and other factors, but on a first gen f-body id like to see this .100-.800 apart. This will give you a decent contact patch between the tire and the road and still allow you to have some fun in the turns.

Positive caster causes camber gains while you turn, which allows you to run less static negative camber which maintains a better contact patch for braking.
I would shoot for as much as you can get while maintaining the camber numbers, I would shoot for 2.0 positive or more. most you can probably get is 3.0, which wont wipe out your tires. This will increase your steering effort too, and get rid of a bit of that "touchy" feel that chevys have with stock steering (way over assisted imo). Be careful with this number on a manual steering car, it can make ita bear on a street car.

Toe. Toe is one of the most critical wear and "pull" angles. In a performance car you want toe out, but it makes it a beast to handle on the highway, on a street car you want toe in. I would need to know your tire size, wheel width and backspacing, and tire type to determine an exact number, but a little bit of toe in is what you want.



Try and find a good racing chassis fab shop inyour area, they will understand what these numbers are and what they do. I agree that good alignment techs are VERY far and few between. Ive only met one other tech that knows what hes doing for alignments. I do my own alignments, my friend showed me how to do it without a machine, and its pretty cool. I should do a write up on it.

69blackwhss
08-21-2011, 11:05 AM
Nice write up here lol an u should do a write up it would be used alot! I drive on the highway the most r to an from work not really back roads alot. Not till I get my ridetech in the mail lol. An the tires are 225/45/17 front an 255/40/17 rear the motor is a BBC rite now but goin ls1 this winter!! Am planing on doing the auto crossing in blowing green just to mess around on 9-10-11, an get some info about do's an don't on ls1 stuff while am there.. If u could give me the numbers that I can take to the shop an get them to do the alignment that u think would work would be great! Don't hurt to try since the stock numbers ain't working for me. An I have power steering also an dose brake on all four corners if u need that info thanks
This car is primarily a street car that sees spirited driving? Ill give you some specs and explain why I chose them.

Camber 1.0-1.25 degrees with "Cross Camber" being a very critical number. You want slightly less camber on the the drivers side, this will compensate for road crown. The amount of difference is determined by the cars suspension type and other factors, but on a first gen f-body id like to see this .100-.800 apart. This will give you a decent contact patch between the tire and the road and still allow you to have some fun in the turns.

Positive caster causes camber gains while you turn, which allows you to run less static negative camber which maintains a better contact patch for braking.
I would shoot for as much as you can get while maintaining the camber numbers, I would shoot for 2.0 positive or more. most you can probably get is 3.0, which wont wipe out your tires. This will increase your steering effort too, and get rid of a bit of that "touchy" feel that chevys have with stock steering (way over assisted imo). Be careful with this number on a manual steering car, it can make ita bear on a street car.

Toe. Toe is one of the most critical wear and "pull" angles. In a performance car you want toe out, but it makes it a beast to handle on the highway, on a street car you want toe in. I would need to know your tire size, wheel width and backspacing, and tire type to determine an exact number, but a little bit of toe in is what you want.



Try and find a good racing chassis fab shop inyour area, they will understand what these numbers are and what they do. I agree that good alignment techs are VERY far and few between. Ive only met one other tech that knows what hes doing for alignments. I do my own alignments, my friend showed me how to do it without a machine, and its pretty cool. I should do a write up on it.

Norm Peterson
08-21-2011, 01:14 PM
225/45-17 is too small of a tire for a V8 F-body, and even more so for a big-block.

Are you still running on original or original-level replacement springs and shocks? The heavier engine will move the suspension further into bump, which momentarily drives your camber further negative than the OE alignment specs anticipated.


For the relatively mild driving that you described, I think you'd get better tire wear with about -0.4° to -0.7° camber, equal on both sides, casters at/slightly more than +2° (set a little cross-caster with the right side slightly higher for road crown compensation instead of using camber). Toe slightly in, around 1/16" (about 0.15°).

You'd want camber more negative than -0.7° for autocross, and for the duration of that activity I'd suggest adding a 1/8" shim to each of the four alignment shim packs as being a good enough correction for starters. FWIW, if you never have autocrossed before, I wouldn't even bother doing that because there are many more important things to focus on before trying to improve the car.


Norm

exwestracer
08-22-2011, 10:04 AM
FWIW, if you never have autocrossed before, I wouldn't even bother doing that because there are many more important things to focus on before trying to improve the car.


Norm

WELL SAID, Norm!

Chad-1stGen
08-22-2011, 11:58 AM
Are you still running on original or original-level replacement springs and shocks? The heavier engine will move the suspension further into bump, which momentarily drives your camber further negative than the OE alignment specs anticipated.
Norm

Never measured it myself but I've heard from respected folks that the first gen camaro actually has *postive* camber gain under compression with stock geometry so I doubt that is his problem.

EDIT: I can say that with stock suspension geometry and 4.0* caster and -1.0* camber I still got very excessive outer tire wear on the track. So I tend to believe that stock first gen suspenion actually gives postive camber gain under compression.

Norm Peterson
08-22-2011, 01:58 PM
That may depend on where the ride height is, relative to OE. I don't have the numbers to plot a rough camber curve, but it's entirely possible for the gain to be positive at the OE design ride height and still nose over into negative-gain territory as the ride height drops. We do know that there's a BB living under the hood, so the ride height may well be lower than stock . . . it's why I asked for that information.

Even if you have negative camber gain in bump from the get-go, it will not normally compensate fully for roll but will be somewhere closer to 50%. The wheel will still go positive relative to the pavement once you're cornering hard enough. 100% roll camber compensation is not desirable for other reasons, and should not be a "goal".


Norm

69blackwhss
08-22-2011, 10:53 PM
Norm, I put a post on here but guess it didn't work. But I have a 2000 454 under the hood with stock small block springs an the wheels are 17x7 225/45/17.... I know the springs are getting bad but I'll be replacing them when I put the ls1 in it soon! But am getting new tires this weekend so I can drive it to the ls fest here in ky on 9-10-11. So if u don't care could u give me some numbers to try that mite help me out on the front end. The guys at the shop said if I had some numbers they do it but other then that they just put it to stock numbers! So any numbers that could help would be great if u need info on other thing plz ask. Thanks jason
That may depend on where the ride height is, relative to OE. I don't have the numbers to plot a rough camber curve, but it's entirely possible for the gain to be positive at the OE design ride height and still nose over into negative-gain territory as the ride height drops. We do know that there's a BB living under the hood, so the ride height may well be lower than stock . . . it's why I asked for that information.

Even if you have negative camber gain in bump from the get-go, it will not normally compensate fully for roll but will be somewhere closer to 50%. The wheel will still go positive relative to the pavement once you're cornering hard enough. 100% roll camber compensation is not desirable for other reasons, and should not be a "goal".


Norm

Norm Peterson
08-23-2011, 07:37 AM
Just how badly are those inner shoulders worn? Any cord showing yet?

Can you measure what your cambers actually are? All you need is something like a digital angle finder that has a bubble level in it, or even a regular level and a small scale (and a calculator with trig functions).

I'd be a lot more comfortable suggesting something slightly more aggressive than the less-negative end of the range I mentioned above in post #8 if I knew that your cambers were a lot more negative than that now.

IMHO, you really need more front tire than a 225-wide with a 1350-ish max load rating. I'm thinking at least 245/45's even for the upcoming LS motor, and that will also call for wider wheels than 7".


Norm

Chad-1stGen
08-23-2011, 10:12 AM
Norm, I put a post on here but guess it didn't work. But I have a 2000 454 under the hood with stock small block springs an the wheels are 17x7 225/45/17.... I know the springs are getting bad but I'll be replacing them when I put the ls1 in it soon! But am getting new tires this weekend so I can drive it to the ls fest here in ky on 9-10-11. So if u don't care could u give me some numbers to try that mite help me out on the front end. The guys at the shop said if I had some numbers they do it but other then that they just put it to stock numbers! So any numbers that could help would be great if u need info on other thing plz ask. Thanks jason

Have you read Dave Pozzi's alignment page? I've seen several people including myself point it out to you. Very good starting point for alignments.

69blackwhss
08-23-2011, 04:17 PM
I don't have any tools like that. ;( an the wires are not showing yet, the true wear is from the inside side wall to about two inch tho the middle of the tire.... An after the ls motor goes in an I get my new ride tech coilovers an their kit on I'll be going with 18x9 up front an a 245/40. Tire. But any numbers that would help put the cental of the true down more would help! Sorry I don't have the tools to help the tires I'll be using will only be ran one season so about 10,000 miles
Just how badly are those inner shoulders worn? Any cord showing yet?

Can you measure what your cambers actually are? All you need is something like a digital angle finder that has a bubble level in it, or even a regular level and a small scale (and a calculator with trig functions).

I'd be a lot more comfortable suggesting something slightly more aggressive than the less-negative end of the range I mentioned above in post #8 if I knew that your cambers were a lot more negative than that now.

IMHO, you really need more front tire than a 225-wide with a 1350-ish max load rating. I'm thinking at least 245/45's even for the upcoming LS motor, and that will also call for wider wheels than 7".


Norm

exwestracer
08-23-2011, 04:20 PM
If you are worried primarily about tire wear, have the camber set at 0. Set the toe at 1/16 in and set the caster at 2 pos. Drive it and see if that fixes the problem.

Yes the stock geometry does have pos camber gain at stock ride height.

69blackwhss
08-23-2011, 04:20 PM
Yes I have read it an it's good info! But that's if u do the update on the upper control arms I believe that's what it says an mines stock. So I didn't wantto go with thoses number if I can find ones that mite work better for me. An thank you for Ur help on here an otter forms ;)
Have you read Dave Pozzi's alignment page? I've seen several people including myself point it out to you. Very good starting point for alignments.

TBART70
08-23-2011, 04:35 PM
If you really don't want to try it yourself (took me 10 to 12 times to get it right) with string and a level (better equipment is available), find a guy who can align the old fashioned way, without the stupid computer pods. Better still, find a guy who's been doing it for about 30 years, and is capable of understanding what camber actually looks like on a wheel--this is not a common talent in today's alignment shop. The main point is this: Most guys who align cars for a living suck at it. Learning how to do it yourself is the best relief, and it's really not that hard. Just be patient, and stay away from chain tire shops.

I do it for a living 25 years, find someone who knows why they are setting to your specs. It's not that hard.

TBART70
08-23-2011, 04:41 PM
Tell them to print out before and after numbers, I did a somewhat stock 67, .5 degree negative camber, I think I got 3 degrees of caster, 1/16" tow in. 16" wheels, good tire wear and it drives real nice.

David Pozzi
08-23-2011, 10:42 PM
I think you may have a worn idler arm, ball joint, A arm bushing or some other problem that is affecting toe. Another item to check is if the car is traveling straight down the road, if the rear axle slips on one side in the rubber spring pads, and is no longer sitting square to the car, then you wind up correcting by steering to one side.
Here are my alignment specs from my web page. You will likely only be able to max caster out to around 3 degrees positive, then set camber to .25 neg, toe in to 1/8". Monitor toe in if you have new springs, as the car settles, the toe will change to toe out so you will have to re-set it. You really can't do alignment or toe settings without turn-tables. I've cheated and tried to do it without them and had terrible results.
David

ALIGNMENT SPECS
David's Specs

Caster 5 deg positive, or as much positive as you can achieve up to 5 deg, can use .5 deg additional positive on the passenger side to compensate for road crown. A common setting would be: LF 5 deg positive, RF 5.5 deg positive.
Camber -.25 degee for mostly freeway driving,
-.5 for street and frequent hard cornering or mountain roads,
-1 deg for street, Autocross, and Open Track, this will wear the inner tire tread if you drive a lot of freeways. I use -1.5 deg quite often on cars that we frequently autox and do only a little street driving. you can use even more if tire temps show outside edge of tread is hotter than inside after a track run. If the inner edges of tread show excessive wear, use less neg camber. An autox only car would use -2 to -3 degrees. If you have not done the Guldstrand mod, you can be more agressive with negative camber and increase neg camber by another -.25 to -.5 degrees.
Toe in, 1/16" to 1/8".

Guldstrand recommends the following specs for a "touring car":

Caster: 3 - 4 degrees positive (+) PS = more, manual steer less.
Camber: 1/4 to 1/2 degrees negative (-)
With upper a-arm relocation Camber: 0 degrees
Toe-in: 0 - 1/8 inch

Guldstrand recomends for racing:

(assumes "Guldstrand mod" is done)

Caster 3 to 4 1/8 deg pos
Camber 1.5 to 2 deg neg
Toe in 1/8" out to 1/8" in (I would try 1/8" out first) more neg camber = more toe out.

Herb Adams recomends these alignment specs for the street:

1 degree positive caster ( I would use 3.5 degrees if PS)
1 degree negative camber.
1/16" toe in

Stock factory alignment specs:

Caster +1/2 deg
Camber + 1/4 to 1/2 deg
Toe-in 1/8" to 1/4" (Radial tires need less toe-in, use 1/8" or less for them)

IN ALL POWER STEERING EQUIPPED CASES, USE AS MUCH POSITIVE CASTER AS YOU CAN ACHIEVE UP TO 5.5 DEGREES POSITIVE MAXIMUM. MORE CASTER HELPS TILT THE WHEEL INWARD WHEN CORNERING, HELPS REDUCE BUMPSTEER BY LOWERING THE TIE ROD ENDS. MANUAL STEER CARS WILL REQUIRE MORE EFFORT AT HIGH CASTER SETTINGS, YOU MAY HAVE TO USE LESS.

69blackwhss
08-25-2011, 09:11 PM
If u could give a some numbers to try out That would be great. I know they use the stock numbers an the inside is bad on my tires so what would I tell them. I just want the front tires to ride more on the center on the tires. Thanks
I think you may have a worn idler arm, ball joint, A arm bushing or some other problem that is affecting toe. Another item to check is if the car is traveling straight down the road, if the rear axle slips on one side in the rubber spring pads, and is no longer sitting square to the car, then you wind up correcting by steering to one side.
Here are my alignment specs from my web page. You will likely only be able to max caster out to around 3 degrees positive, then set camber to .25 neg, toe in to 1/8". Monitor toe in if you have new springs, as the car settles, the toe will change to toe out so you will have to re-set it. You really can't do alignment or toe settings without turn-tables. I've cheated and tried to do it without them and had terrible results.
David

Chad-1stGen
08-26-2011, 08:29 AM
If u could give a some numbers to try out That would be great. I know they use the stock numbers an the inside is bad on my tires so what would I tell them. I just want the front tires to ride more on the center on the tires. Thanks

A correctly aligned car using STOCK settings will NOT wear the inside of your tire. Either the alignment was done incorrectly or you have worn parts causing the alignment problem. Reading this thread its like everyone is talking to a wall...

David Pozzi
08-26-2011, 10:24 PM
I agree, you either have worn suspension parts or the alignment was done wrong. OR as I said, if the car settles it will toe out and wear the tires on the inside edges. If the wear is on the right front, the idler arm has a lot do do with RF toe.

Stock alignment numbers are not the greatest for performance handling with wider than stock tires, but your tires should not wear on the inside shoulders if aligned to factory specs, it just won't corner as well as it could.
I gave you alignment specs above. You can run more or less camber depending on how hard you expect to drive the car around turns.

You will likely only be able to max caster out to around 3 degrees positive, then set camber to .25 neg, toe in to 1/8".