toe-in, just to be sure..
05-14-2018, 08:20 PM
#23
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St. Jude Donor '07
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.
Bill
05-14-2018, 09:10 PM
#24
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You are wrong and I am right. Total toe, either negative or postive is measured ONLY in front of the wheels, either front or rear.
Total toe is the sum of the left and right wheels, additive.
If you're talking this degree stuff and not fractions in settings, I know nothing about this set up.
You can easily look this stuff upin the factory shop manuals.
Total toe is the sum of the left and right wheels, additive.
If you're talking this degree stuff and not fractions in settings, I know nothing about this set up.
You can easily look this stuff upin the factory shop manuals.
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GTOguy (05-15-2018)
05-14-2018, 11:47 PM
#25
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St. Jude Donor '07
from:
http://free-ed.net/sweethaven/mechte...s.asp?iNum=126
Figure 12-53 — Tram gauge.
The procedures for using a tram gauge for measuring toe are as follows:
Raise the front wheels of the vehicle and rub a chalk line all the way around the center rib on each tire.
With a scribing tool, rotate each tire and scribe a fine line on the chalk line. This will give you a very thin reference line for measuring the distance between the tires.
Lower the vehicle back on the turning radius gauges.
Position the tram gauge at the back of the tires. Move the pointers until they line up with the scribe marks on the tires.
Without bumping the tram gauge pointers, reposition the gauge to the front of the tires. The difference between the lines on the front and rear of the tires shows toe.
If the lines on the front of the tires are closer together than on the rear, the wheels are toed-in. If the lines are the same distance apart at the front and rear, toe is zero. Use the manufacturer’s service manual for specifications and adjustment procedures.
Bill
http://free-ed.net/sweethaven/mechte...s.asp?iNum=126
Figure 12-53 — Tram gauge.
The procedures for using a tram gauge for measuring toe are as follows:
Raise the front wheels of the vehicle and rub a chalk line all the way around the center rib on each tire.
With a scribing tool, rotate each tire and scribe a fine line on the chalk line. This will give you a very thin reference line for measuring the distance between the tires.
Lower the vehicle back on the turning radius gauges.
Position the tram gauge at the back of the tires. Move the pointers until they line up with the scribe marks on the tires.
Without bumping the tram gauge pointers, reposition the gauge to the front of the tires. The difference between the lines on the front and rear of the tires shows toe.
If the lines on the front of the tires are closer together than on the rear, the wheels are toed-in. If the lines are the same distance apart at the front and rear, toe is zero. Use the manufacturer’s service manual for specifications and adjustment procedures.
Bill
05-15-2018, 12:36 AM
#26
Drifting
Mike is correct again, sorry to say 
What Bill has posted above is just a simplistic determination of whether there is toe in or toe out; note that it refers us to the vehicle service manual for actual measurements.
That's why it's called TOE, not HEEL AND TOE
Total toe is just the sum of both sides.
What Bill has posted above is just a simplistic determination of whether there is toe in or toe out; note that it refers us to the vehicle service manual for actual measurements.
That's why it's called TOE, not HEEL AND TOE
Total toe is just the sum of both sides.
Last edited by SW Vette; 05-15-2018 at 12:37 AM.
05-15-2018, 01:54 AM
#27
Melting Slicks
Thread Starter
still, my original question is not answered
: if a manual says to dial in 1/32" of toe-in, what do they refer to?
: if a manual says to dial in 1/32" of toe-in, what do they refer to?
05-15-2018, 03:32 AM
#28
Drifting
Assuming that is a "per side" spec, it means the front of each wheel should be 1/32" IN from parallel to the vehicle centerline, resulting in "total" toe-in of 1/16".
05-15-2018, 04:16 AM
#29
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St. Jude Donor '07
Mike is correct again, sorry to say
What Bill has posted above is just a simplistic determination of whether there is toe in or toe out; note that it refers us to the vehicle service manual for actual measurements.
That's why it's called TOE, not HEEL AND TOE
Total toe is just the sum of both sides.
What Bill has posted above is just a simplistic determination of whether there is toe in or toe out; note that it refers us to the vehicle service manual for actual measurements.
That's why it's called TOE, not HEEL AND TOE
Total toe is just the sum of both sides.
generically, I don't have a clue... all I have ever done is use a tram or tape to set total toe and then adjust side-to-side (if necessary) in order to center the steering wheel
I found this as an explanation of how to interpret the meaning of the amount of toe from the manufacturers specs:
http://aligncraft.com/terms/terms.html#Front toe
Measuring Toe
Toe on an individual tire/wheel assembly is understood to be the difference between the distance of the front and rear of one tire in reference to the vehicle centerline. Since most alignment specifications show toe as total toe, i.e. both wheels, it is important to understand two points: (1) 1/2 of the specified total toe should be applied to each front wheel. (2) a minus(-) sign would actually indicate a toe-out setting as being specified. It is important to note that although toe has historically been measured as a distance in fractions of an inch, and then decimal inches, it is becoming more common for vehicle manufacturers to express toe in degrees. The idea is that the angle, rather than an arbitrary distance, determines the side slip of the tire and the resulting scrub of the tread. This should not be affected by the tire size, but rather should be constant for a given measurement. Most alignment equipment displays toe-out as a minus (-) and toe-in as a positive (+).
Bill
I will concede that Mike is correct in explaining what toe is (the relationship between B & C), and I will maintain that measuring A & C is a way of actually determining and getting there for those who do not have access to sophisticated alignment equipment as there is no other practical way of determining the steering axis of rotation of the wheel.
Last edited by wmf62; 05-15-2018 at 05:05 AM.
05-15-2018, 07:42 AM
#30
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If your info says to set your toe in at 1/32, that means 1/32 on each wheel, which means between the two tires, you now have 1/16 toe in, total from the vehicle center line.
If you are setting your toe in in your driveway, using a tram gauge on the front and rear side of the tire will assist you in finding the actual track width. It won't tell you where the vehicle center line is.
The best thing to do is forget all this stuff and take your vehicle to an alignment shop that can do a four wheel alignment that establishes the correct thrust angle. I don't know how you can duplicate this with a string and/or a tram gauge.
https://www.knowyourparts.com/techni...-thrust-angle/
Last edited by MikeM; 05-15-2018 at 07:43 AM.
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6T5RUSH (05-15-2018)
05-15-2018, 07:53 AM
#31
Team Owner
When my trailing arms are re-bushed you can bet I'm off to Mssr. Malone to get the job done right...
05-15-2018, 08:14 AM
#32
Melting Slicks
Thread Starter
It's been answered several times in confusing ways. Never mind the term "total toe".
If your info says to set your toe in at 1/32, that means 1/32 on each wheel, which means between the two tires, you now have 1/16 toe in, total from the vehicle center line.
https://www.knowyourparts.com/techni...-thrust-angle/
If your info says to set your toe in at 1/32, that means 1/32 on each wheel, which means between the two tires, you now have 1/16 toe in, total from the vehicle center line.
https://www.knowyourparts.com/techni...-thrust-angle/
So if a spec says 1/32" toe-in , it means 1/32" inch against the car centreline and measured from wheel center to tire edge. Is this picture correct then?
05-15-2018, 08:39 AM
#34
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St. Jude Donor '07
read # 30s bold quote. unless the quote is wrong, I interpret it that toe-in specs are given as 'total', unless otherwise noted as individual. if that's the case, then your sketch depicted as 1/32 each side would be a 1/16th toe spec.
everyone is right about one thing; take it to an expert
Bill
05-15-2018, 08:46 AM
#35
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Bill
05-15-2018, 08:49 AM
#36
Team Owner
I'm not worried..
05-15-2018, 08:52 AM
#37
Melting Slicks
Thread Starter
the confusion is not getting any clearer...
read # 30s bold quote. unless the quote is wrong, I interpret it that toe-in specs are given as 'total', unless otherwise noted as individual. if that's the case, then your sketch depicted as 1/32 each side would be a 1/16th toe spec.
everyone is right about one thing; take it to an expert
Bill
read # 30s bold quote. unless the quote is wrong, I interpret it that toe-in specs are given as 'total', unless otherwise noted as individual. if that's the case, then your sketch depicted as 1/32 each side would be a 1/16th toe spec.
everyone is right about one thing; take it to an expert
Bill
Besides that, it's quite disturbing to have scrolled through tens of threads on wheel alignment where members argue about small and precise alignement tweaks, and now learning that there is no common understanding/definition and can have those numbers change by a factor of 2
Last edited by alexandervdr; 05-15-2018 at 08:54 AM.
05-15-2018, 09:00 AM
#38
I'm all about strings, levels and toe-in gauges these days.
When doing a 4 wheel alignment on these old, not precision built cars. Do they go off the body or the chassis to get the right thrust angles?
I recently did my CTS coupe using the body rocker pinch welds and got good results, but these cars being uni-body make this less complicated.
When doing a 4 wheel alignment on these old, not precision built cars. Do they go off the body or the chassis to get the right thrust angles?
I recently did my CTS coupe using the body rocker pinch welds and got good results, but these cars being uni-body make this less complicated.
05-15-2018, 09:00 AM
#39
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St. Jude Donor '07
The reason I want to know is that there are no expert around where I live...
Besides that, it's quite disturbing to have scrolled through tens of threads on wheel alignment where members argue about small and precise alignement tweaks, and now learning that there is no common understanding/definition and changes those numbers by a factor of 2
Besides that, it's quite disturbing to have scrolled through tens of threads on wheel alignment where members argue about small and precise alignement tweaks, and now learning that there is no common understanding/definition and changes those numbers by a factor of 2
I apologize if I've added to the confusion... all I know for sure is how I have set alignment using hand tools.
and, i'm sure I've added to the confusion by arguing about what toe-in is by mixing in how I set toe-in.
66RBS's info (post 34) from the AIM seems to correlate with what I believe toe-in specs to be specified as, unless noted otherwise; total toe. with each wheel being 1/2 of that distance from the axial centerline of rotation...
take all we've said into consideration, and let Google and the manufacture's instructions be the referee. I think we're all talking about the same thing but from different directions......
Bill
Last edited by wmf62; 05-15-2018 at 09:05 AM.
05-15-2018, 09:32 AM
#40
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If the front wheels are straight/parallel with the car center line, you have 0 toe. Period!
If you have one tire toed in a 1/32" and the other straight/parallel with the car, you have 1/32" total toe or 1/32" toe on one wheel. Theoretically, in a perfect world, this will throw your steering wheel clear vision off center.
If you have both the left and right wheels toed in 1/32" each from the car center line, you now have a total toe in of 1/16".
In all cases, whatever toe in you have at the front of the wheels should be equally matched as toe outon the back side of wheel unless something is bent. One dimension should cancel the other in relation to car center line.
You are way overthinking something that is very simple.
Last edited by MikeM; 05-15-2018 at 09:38 AM.
