toe-in, just to be sure..
#1
Melting Slicks
Thread Starter
toe-in, just to be sure..
When specs state to have a toe-in of say 1/32", do they mean the difference between A and B (which is what I always used) or A and C?
#2
Team Owner
A to C
#3
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#4
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Yes. Think of all 4 tires on two parallel planes....deviation from those planes will result in a change in toe angle. So zero toe would be all 4 tires parallel. Toe in would be as pictured. Toe out, the opposite.
#5
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It's the difference between A and B. If B was 48" and A was 47 1/2", you'd have a half inch of positive toe on the front wheels. That's total toe, not necessarily the same on each wheel.
#6
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Mike M is 100% correct.....'B' is a never-changing measurement...as the axle or hub, it is the center point of the wheel, which is the plane that pivots. . When doing an alignment check and performing a 'steering axis inclination test' (or kingpin axis inclination test as it was called in the '50's), if 'B' is different side to side, it is an indication of a bent steering arm, etc.
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#9
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No, it's the difference between B and C. I typed the wrong letter in.
A has nothing to do with the total toe.
A has nothing to do with the total toe.
Last edited by MikeM; 05-14-2018 at 05:00 PM.
#11
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Mike is right. The measurement of B never changes. Because toe-in and toe-out is measured at the front of the tire, not the rear.
#12
Drifting
Last edited by Mossy66; 05-14-2018 at 05:16 PM.
#13
Race Director
Isn’t the spec of 1/32 for each side? They are adjusted and set separately.
So wouldn’t the correct measurement in the way the OP asked the question be “none of the above”?
I think it would be (B - C)/2
C is toe in at the front of the tire, A is at the back of the tire and irrelevant.
So wouldn’t the correct measurement in the way the OP asked the question be “none of the above”?
I think it would be (B - C)/2
C is toe in at the front of the tire, A is at the back of the tire and irrelevant.
#14
Le Mans Master
In the "OLD" days, this led to some interesting conversations with the alignment tech who was aligning both front and rear wheels on my C2 race car, because I had to back the car onto the alignment machine in order to measure rear toe. This meant (rear facing) that the rear toe (IN) was measured as "toe OUT" at the rear of each rear wheel.
Last edited by 63Corvette; 05-14-2018 at 05:20 PM.
#15
Team Owner
Depends on the number you're looking. If you want total toe, it's the difference between a and C
Last edited by 65GGvert; 05-14-2018 at 05:23 PM.
#16
Melting Slicks
Thread Starter
#18
Race Director
So - to clarify - is that 1/32 toe per side, or total toe?
I thought it was per side?
I thought it was per side?
#19
Race Director
I think there are two realities here. If you are working on a proper alignment rack then it's B & C and it will tell you toe in/out in fractions of inch or degrees. If you are a do-it-yourselfer in your home garage with a tram gage - then it's A & C because that's what the gage measures. A tram gage is limited in what it can do and not as accurate. And a tram gage will only determines total toe in/out and not individual wheel toe in/out.
Last edited by DansYellow66; 05-14-2018 at 07:03 PM.
#20
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