70 Alignment Specs
07-17-2003, 10:14 PM
#1
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Thread Starter
70 Alignment Specs
I am going in the morning to get an alignment done. I was wondering are the alignment specs the same for the 70 and 82. The shops computer doesn't go back to 1970 specs so I told him the 82 specs were the same. Is this okay? I just want to drive in a straight line and do no autocrossing.
Thanks for any answers.
Thanks for any answers.
07-18-2003, 12:36 AM
#3
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Re: 70 Alignment Specs (Eddie 70)
Recommended Specs by Vette Brakes Inc.
Toe: (total of both sides) should be at zero or just slightly toed in, no more than 1/8" absolute max. They recommend just 1/32". Basically, you're shooting for as near zero as you can get, given the uncertainty in the measurements, while being sure not to go "toe out". If the car will track in a straight line on a level road, and it measures essentially zero toe, you're exactly where you want to be. That's easy. However, I would get the camber/caster right first, because adjusting them will alter the toe reading a little.
Camber: VB recommends that (just like the toe-in) you shoot for zero camber.
Caster: VB recommends 2.75 degrees positive caster. You get caster by moving the upper ball joint rearward, which happens by adding shims to the rear shaft bolt and/or subtracting shims from the front shaft bolt.
Take a close look at the four sets of shims (two sets per side) that are on those shaft bolts. Make sure the shims are between the shaft and the frame. It wouldn't be the first time somebody put the shims on the wrong side of the shaft. (Don't ask me how I know. ) Take a close look at the mounting bolts for the lower control arm shafts. Those shafts should be sitting squarely on the frame, with no washers or whatever between the shaft and the frame.
Vette Brakes recommends for daily driver:
Front:
Toe 1/32" in
Camber 0 deg neg
Caster 2.75 deg pos
Rear:
Toe 1/8" in
Camber 0 deg neg
-------------------------------------------------------------------------------------------------
Recommendation for Radial Tires is:
Front:
Toe-in 1/16"
Camber 0 to -1/2
Caster +1.5 to +2.0
Rear:
Toe-in 1/32" each side, 1/16" total
Camber -1/2 to -1
If you drive in a sporting manner go toward the "more negative" end of the camber specs. Greater positive caster will provide more "on center" steering feel, but make slow speed steering harder. If you have power steering go with two degrees. Cross camber and caster should be as close to zero as possible.
If you don't push the limit of the handling envelope, go with Wayne's camber specs.
The big issue in Corvette alignment is the rear toe. It's easy to measure the total. The trick is determining if is is properly divided - one half of the total on each side. Discuss this issue with your alignment tech.
Also, if he has to change rear toe shims he should understand what he's up against if the car has the fully captured type shims that require removal of the trailng arm bolts to change.
The above toe-in specs are for radial tires. For bias ply tires the toe should be set at the nomimal factory spec in the service manual.
[Modified by Barry's70LT1, 12:46 PM 7/18/2003]
Toe: (total of both sides) should be at zero or just slightly toed in, no more than 1/8" absolute max. They recommend just 1/32". Basically, you're shooting for as near zero as you can get, given the uncertainty in the measurements, while being sure not to go "toe out". If the car will track in a straight line on a level road, and it measures essentially zero toe, you're exactly where you want to be. That's easy. However, I would get the camber/caster right first, because adjusting them will alter the toe reading a little.
Camber: VB recommends that (just like the toe-in) you shoot for zero camber.
Caster: VB recommends 2.75 degrees positive caster. You get caster by moving the upper ball joint rearward, which happens by adding shims to the rear shaft bolt and/or subtracting shims from the front shaft bolt.
Take a close look at the four sets of shims (two sets per side) that are on those shaft bolts. Make sure the shims are between the shaft and the frame. It wouldn't be the first time somebody put the shims on the wrong side of the shaft. (Don't ask me how I know. ) Take a close look at the mounting bolts for the lower control arm shafts. Those shafts should be sitting squarely on the frame, with no washers or whatever between the shaft and the frame.
Vette Brakes recommends for daily driver:
Front:
Toe 1/32" in
Camber 0 deg neg
Caster 2.75 deg pos
Rear:
Toe 1/8" in
Camber 0 deg neg
-------------------------------------------------------------------------------------------------
Recommendation for Radial Tires is:
Front:
Toe-in 1/16"
Camber 0 to -1/2
Caster +1.5 to +2.0
Rear:
Toe-in 1/32" each side, 1/16" total
Camber -1/2 to -1
If you drive in a sporting manner go toward the "more negative" end of the camber specs. Greater positive caster will provide more "on center" steering feel, but make slow speed steering harder. If you have power steering go with two degrees. Cross camber and caster should be as close to zero as possible.
If you don't push the limit of the handling envelope, go with Wayne's camber specs.
The big issue in Corvette alignment is the rear toe. It's easy to measure the total. The trick is determining if is is properly divided - one half of the total on each side. Discuss this issue with your alignment tech.
Also, if he has to change rear toe shims he should understand what he's up against if the car has the fully captured type shims that require removal of the trailng arm bolts to change.
The above toe-in specs are for radial tires. For bias ply tires the toe should be set at the nomimal factory spec in the service manual.
[Modified by Barry's70LT1, 12:46 PM 7/18/2003]
08-06-2017, 09:45 PM
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St. Jude Donor '08-'09-'10-'11-'12-'13-'14-'15
I'm sorry, I posted in the wrong thread.... and bumped an older than heck thread... My sincere apologies.
Last edited by Willcox Corvette; 08-06-2017 at 09:46 PM.
