Rear toe settings, Rear toe settings Options

[rhd914]

Hi, well at long last my project car is almost complete. It came off the road in 2006 for a lot of reason. The car is now complete again and has a nice 3.2 in it along with a host of other upgrades.
I have just fitted Michelin pilot sport 3 front and rear.
I want to send it for an alignment, but the spec for the rear toe in settings are in degree.
Can anyone tell me what the setting is in millimeters?
Thanks
Geoff

[messix]

use this to convert, http://www.onlineconversion.com/forum/forum_1061942119.htm


degrees is a constant regardless of distance or length. [tire diameter]

that's is why the "degree" is the universal alignment standard.

[r_towle]

Tire diameter is required when using inches or MM measurements.
The machine should be using degrees, not MM measurements, regardless of what part of the world you reside.

Look at the factory manual, the numbers are in degrees.

At the end of the day, you want almost just a hair of toe in at the rear.

Rich

[stugray]

At the end of the day, you want almost just a hair of toe in at the rear.

I assume you mean Toe IN ;-)

As for the measurement it is:
Wheel Diameter (mm)= WD
Angle of Toe (degrees) = AT
Distance of Toe = DT (mm)

DT = WD * SIN(AT)

So for a 15 inch rim (15 inches = 381mm)
And One degree of Toe:

DT = 381(mm) * SIN(1.0) = 381 * 0.01745 = 6.65 mm

So for every degree of Toe-IN (near zero) you would space the forward rim of the wheel IN by ~6.6mm (or ~ 1/4 inch)

Stu

[sixnotfour]

Factory setting is below, thanks to Bowlsby

15 minutes is .25 of a degree
20 minutes is .333 of a degree
30 minutes is .50 of a degree

[SirAndy]

Can anyone tell me what the setting is in millimeters?

Millimeters will be different depending on your wheel size, so no, there is no easy answer.

If you are using strings to align the car and measuring mm from the lip of the wheel to the string, you need to do the math (distance from the axle center to your wheel lip) and calculate the the mm that give you a certain degree of toe (in or out).


However, if this is for a street car, i'd just set it to 0 degrees ...
(IMG:style_emoticons/default/shades.gif)

[r_towle]

At the end of the day, you want almost just a hair of toe in at the rear.

I assume you mean Toe IN ;-)

You can read, right?
Might want to do that first.

[r_towle]

Can anyone tell me what the setting is in millimeters?

Millimeters will be different depending on your wheel size, so no, there is no easy answer.

If you are using strings to align the car and measuring mm from the lip of the wheel to the string, you need to do the math (distance from the axle center to your wheel lip) and calculate the the mm that give you a certain degree of toe (in or out).


However, if this is for a street car, i'd just set it to 0 degrees ...
(IMG:style_emoticons/default/shades.gif)

(IMG:style_emoticons/default/agree.gif)

Rear can be zero...works better for a street car.
To much toe IN at the rear makes the car really darty, and you get sucked around in ruts the trucks leave on the highways.

More toe IN helps on an autox car...helps turn the car in quickly.

[stugray]

You can read, right?

Sorry, when I read that my brain registered:

At the end of the day, you want almost just a hair of toe in the rear.

AND since I have been measuring the TOE "in the rear" on my car the last few days AND IT is toed OUT, I am also interested in the subject.

Stu

[TravisNeff]

toe in makes the car more stable in a straight line, toe out makes the car want to turn!

[Downunderman]

Geoff, I run about 1 - 1.5 mm per side toe in on the rear. Seems to work pretty well.

[jimkelly]

I assume you guys do this with car on ground with wheels/tires on.

loosen the bolts some, and tap the bracket toward the wanted position?

or does this have to be done with car off the ground?

jim

[Bartlett 914]

If you are using strings to align the car and measuring mm from the lip of the wheel to the string, you need to do the math (distance from the axle center to your wheel lip) and calculate the the mm that give you a certain degree of toe (in or out).

If you are using Stu's numbers then the measurement would be the difference between the rear of the rim to the front of the rim measured at the center line of the wheel. If you are measuring from the axle to the rim, Stu's numbers are double the number you need.

[Dave_Darling]

To much toe IN at the rear makes the car really darty, and you get sucked around in ruts the trucks leave on the highways.

More toe IN helps on an autox car...helps turn the car in quickly.

Wrong way around. It's toe OUT at the front that can help initial turn-in. And makes the car darty.

Toe OUT at the rear of the car is pretty diabolical. It means the tail of the car will like to step out, and will try to keep going once it starts sliding. Not so good...

--DD

[sixnotfour]

Geoff, I run about 1 - 1.5 mm per side toe in on the rear. Seems to work pretty well

measured where ??

[r_towle]

To much toe IN at the rear makes the car really darty, and you get sucked around in ruts the trucks leave on the highways.

More toe IN helps on an autox car...helps turn the car in quickly.

Wrong way around. It's toe OUT at the front that can help initial turn-in. And makes the car darty.

Toe OUT at the rear of the car is pretty diabolical. It means the tail of the car will like to step out, and will try to keep going once it starts sliding. Not so good...

--DD

No, you have it wrong.

Fr auto cross.
Toe out in front, toe in in the rear, both more than a street car.
Car turns in fast.....sucks to drive on the road, you need to hold on tight to the wheel.

Rich

[Dave_Darling]

Read it again, Rich.

Toe OUT in front, better turn in but the car is darty. OK for autoX, bad for the street and a bit of a handful on the big track.

If you toe OUT in the back, the car goes sideways all the time. You don't want that.

Street: Toe in at the front, toe in at the rear.
AutoX: Toe out at the front, toe in at the rear.
Big track: Toe in at the front, toe in at the rear.

--DD

[rhd914]

Hi and thanks for the reply's. I was looking for a reading in mm as the printout from the tyre shop gave the reading in mm. So I guess I will make a calculation and work out what I need them to set it at.
I am thinking this one is a little beyond them. I am going to look for someone else to do this.
Love the info I have learnt a lot from this.
My area is wires so I am loving the chance to learn some more.
Geoff