Sponsored

is -.30 total rear toe too much?

RadBOSS

Well-Known Member
Joined
Apr 30, 2016
Threads
2
Messages
159
Reaction score
40
Location
Paso Robles, CA
Vehicle(s)
69 BOSS302, 29 Model A Roadster
This cannot be correct. You know, the reason it's called toe-in and out is because it's the same as looking down at your toes and pointing them in or out.

Positive toe is when they point outward.

EDIT: I think I figured out what the problem is. The second thing cited (from tirerack) says "positive toe-in". But that's misleading. There's positive and negative toe. Or toe-in and toe-out. Conflating both leads to confusion.

Toe-in - definition of toe-in by The Free Dictionary
www.thefreedictionary.com/toe-in
toe-in (tō′ĭn′) n. An inwardly angled adjustment, especially a slight inward alignment of the forward edge of a motor vehicle's front wheels to improve steering ...

Here s another technical source with compelling graphics:

http://www.motoiq.com/MagazineArtic...and-Handling-Part-Seven--Tuning-your-Toe.aspx
Sponsored

 

Stuntman

Well-Known Member
Joined
Dec 12, 2013
Threads
5
Messages
1,448
Reaction score
488
Location
SoCal
Vehicle(s)
many
I am not aligned to OEM spec. I am aligned IAW FP road course recomended specs provided with the GT350 supplement package.
My rear tires are toe in / \, I can see it and I measured to verify.
From your Hunter Alignment sheet, you have Toe-OUT ( \ / ) in the rear. Every hunter alignment machine reads Toe-OUT as negative and toe-in positive.

YOU HAVE TOE-OUT IN THE REAR -which is not safe. No rwd street or track car does this.

I called FP and they said the FP alignment sheet has a type-o and it should be toe IN at the rear.

Please fix your alignment asap.


What was your method of measuring it and what were the numbers?
 
Last edited:
OP
OP
Zitrosounds

Zitrosounds

Well-Known Member
Joined
Oct 20, 2015
Threads
67
Messages
3,407
Reaction score
2,164
Location
Madison, AL
First Name
Harold
Vehicle(s)
16 GT350R/16 GT350TP/15 GT-PP/12 GT-PP
:clap2:I think you've answered your own question.
I was looking for more insight on tire wear and that is why I posed the question in my initial post. I do not daily drive the car but the car does see more street than track.
 

Stuntman

Well-Known Member
Joined
Dec 12, 2013
Threads
5
Messages
1,448
Reaction score
488
Location
SoCal
Vehicle(s)
many
From your alignment sheet. Looks like you dropped your car a little. This caused front toe to move from toe-in to toe-out. Rear toe moved outward but still toe-in. The alignment shop corrected the front toe. But then misaligned the rear. You have toe-out at the moment. GT toe is 0.12* +/- 0.20* which is 0.32* toe-in to -0.08* toe-out. If you read the alignment printout in small number is says "-0.09*" & "0.32*" with middle therefore being 0.12 (it's not written, only a line). Your rear toe boxes are RED meaning they are outside of factory spec at "-0.16". This is toe-out and out of spec.

If you look at the printout. Each box has a center and 2 steps. Center is on spec. First step in the correct direction is usual good. Outside of second step is bad and causes the box to turn red.

You can align to GT350R specs which is still mostly toe-in. 0.15* +/- 0.20* or 0.35* in to -0.05* out. (But it don't see what's wrong with -0.09* out if machine says it's limit).

The real question Is how does toe-in and toe-out change the handling of the car?
You need to look at the Total/split which is 0.30 +/- 0.20

The TOTAL toe range for the GT350/R is 0.10-0.50 toe-IN


(The 0.15 +/- 0.20 is PER side. So there is an allowance to have the rear toe staggered, birthday total needs to always be Toe-IN).
 
OP
OP
Zitrosounds

Zitrosounds

Well-Known Member
Joined
Oct 20, 2015
Threads
67
Messages
3,407
Reaction score
2,164
Location
Madison, AL
First Name
Harold
Vehicle(s)
16 GT350R/16 GT350TP/15 GT-PP/12 GT-PP
From your Hunter Alignment sheet, you have Toe-OUT ( \ / ) in the rear. Every hunter alignment machine reads Toe-OUT as negative and toe-in positive.

YOU HAVE TOE-OUT IN THE REAR -which is not safe. No rwd street or track car does this.

I called FP and they said the FP alignment sheet has a type-o and it should be toe IN at the rear.

Please fix your alignment asap.


What was your method of measuring it and what were the numbers?
I am not pretending to be an alignment expert nor do I know how to use the hunter machine. I am suspect of the print out or the setup of the equipment on the car. I measured the rear and the distance between front of rear tires is less of that in the rear / \. Shop opens at 8am and I will be speaking with the tech to clarify. I specifically asked for toe in per the spec sheet regardless of the negative symbol in front of the .30. Again, I am not an expert in alignment but I know enough to get my self in trouble. Now I really feel I should have finished the alignment at home. Like I said, I did not perform the alignment so I had no control measures during the alignment setup and readings. Thank you all for your insight.will keep you posted in what the shop tech says.

H
 
Last edited:

Sponsored

Stuntman

Well-Known Member
Joined
Dec 12, 2013
Threads
5
Messages
1,448
Reaction score
488
Location
SoCal
Vehicle(s)
many
I am not pretending to be an alignment expert nor do I know how to use the hunter machine. I am suspect of the print out or the setup of the equipment on the car. I measured the rear and the distance between front of rear tires is less of that in the rear / \. Shop opens at 8am and I will be speaking with the tech to clarify. I specifically asked for toe in per the spec sheet regardless of the negative symbol in front of the .30. Again, I am not an expert in alignment but I know enough to get my self in trouble. Now I really feel I should have finished the alignment at home. Like I said, I did not perform the alignment so I had no control measures during the alignment setup and readings. Thank you all for your insight.will keep you posted in what the shop tech says.

H
How did you measure the alignment yourself exactly?

You might want to look at the first few pages of the Hunter manual:

https://www.google.com/url?sa=t&sou...fhLq4acrhY0B5Y0-g&sig2=5eQ1IL4JTETSLq3eNl5FoA

Please do.
 
OP
OP
Zitrosounds

Zitrosounds

Well-Known Member
Joined
Oct 20, 2015
Threads
67
Messages
3,407
Reaction score
2,164
Location
Madison, AL
First Name
Harold
Vehicle(s)
16 GT350R/16 GT350TP/15 GT-PP/12 GT-PP

TheDeadCow

Just some guy
Joined
Apr 17, 2016
Threads
9
Messages
602
Reaction score
376
Location
Gilbert, Arizona
First Name
Mike
Vehicle(s)
Hot Rod
Vehicle Showcase
1
I was looking for more insight on tire wear and that is why I posed the question in my initial post. I do not daily drive the car but the car does see more street than track.
Oh ok, lol.

I assume the track alignment is like a "baseline" setup. A baseline setup is just a neutral setup or place to start for any track. I wouldn't expect excessive tire wear from this setup. If it was too much rear toe you'd notice graining somewhere on the contact patch of the rear tires along with undesirable handling characteristics which you've already defined.

When you go to the track ask some people who seem knowledgeable about it. You can learn a lot talking to people in the pits. :D
 

Stuntman

Well-Known Member
Joined
Dec 12, 2013
Threads
5
Messages
1,448
Reaction score
488
Location
SoCal
Vehicle(s)
many
I used jack stands, stiring, level and tape measure to verify toe
So strings parallel to each other along the side of the car then measure the distance from the string to the lip of the front of the wheel then from the string to the lip of the back of the wheel?

If so, which measurement was longer and by how much?
 
OP
OP
Zitrosounds

Zitrosounds

Well-Known Member
Joined
Oct 20, 2015
Threads
67
Messages
3,407
Reaction score
2,164
Location
Madison, AL
First Name
Harold
Vehicle(s)
16 GT350R/16 GT350TP/15 GT-PP/12 GT-PP
So strings parallel to each other along the side of the car then measure the distance from the string to the lip of the front of the wheel then from the string to the lip of the back of the wheel?

If so, which measurement was longer and by how much?
The front measurement was larger than the rear wheel meaaurement. Don't remember, didnt jot it down as it was just for reference. I had my wife double check me, she loves mathematics specifically geometry.
 

Sponsored
OP
OP
Zitrosounds

Zitrosounds

Well-Known Member
Joined
Oct 20, 2015
Threads
67
Messages
3,407
Reaction score
2,164
Location
Madison, AL
First Name
Harold
Vehicle(s)
16 GT350R/16 GT350TP/15 GT-PP/12 GT-PP
Sounds right. Then I'm dumbfounded in regards to your printout.
I am dumbfounded as well but I guess I'm not surprised. I was real specific about tq values of all the hardware loosened and adjusted for the alignment. Needless to say when I returned home I checked the hardware and nothing was torqued. I already spoke to the manager about the hardware and the printout issue. I have an appointment at 1 p.m.
 

JAJ

Well-Known Member
Joined
Apr 9, 2016
Threads
4
Messages
2,226
Reaction score
1,983
Location
Vancouver BC
Vehicle(s)
2016 GT350 Track Pack
I string mine too. A pro crew chief I talked to once said that in his race shop, he uses a laser alignment machine to set up customer cars. But he uses string on the race car because it's just as accurate and it's a lot more reliable because there's nothing to go wrong.
 

Ctease

Well-Known Member
Joined
Feb 7, 2017
Threads
0
Messages
175
Reaction score
81
Location
Texas
Vehicle(s)
GT350

RadBOSS

Well-Known Member
Joined
Apr 30, 2016
Threads
2
Messages
159
Reaction score
40
Location
Paso Robles, CA
Vehicle(s)
69 BOSS302, 29 Model A Roadster
So strings parallel to each other along the side of the car then measure the distance from the string to the lip of the front of the wheel then from the string to the lip of the back of the wheel?

If so, which measurement was longer and by how much?

Is the front and rear track really the same? The tires and wheels are certainly not the same width front to rear. You are not set up correctly. Your string has to be parallel to the centerline of the chassis, not to the wheels.
Sponsored

 
Last edited:
 








Top