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RJacobsen
June 11th, 2009, 09:51 AM
This might be one of those dumb questions but here goes. the rear toe in is listed as 1/32 per side or 1/16 total, my guess is that the measurement is taken at the outer diameter of the tire but I can't confirm this in any search I've done. If the measurement is taken anywhere closer to the hub center, the angle changes considerably.
appriciate the help.

Aggressor
June 11th, 2009, 12:41 PM
Rod, From what I've seen the toe angle is measured on the outside tire diameter. The toe measurement would change the actual toe angle considerably with widely varying tire diameters. On a very large diameter tire a 1/16th toe would proportionally be a very small toe angle while on a stock vintage 60's Mini Cooper tire it would be a signifigantly larger angle.

The most basic way to check toe is to jack the car up and spin the tire. A scribed a line is then created on the tire by lightly touching it's spinning outer surface with a sharp instrument. The car is then lowered and rolled out on a flat surface allowing the suspension to settle and the wheels to be set straight as possible. The front and rear toe is measure at the wheel centerline height and the difference is your toe figure.

I think that most of us are running between 255/60-295/50 series tires in the rear. The diameter difference is about 1.3 inches or .65 radius for this range. I'm inclined to believe that until we're jackin them up with two foot lift kits and using genuuwhine big foot tars(In my best hillbilly accent) , the difference may be negligible.

-Geary

PS If you think I'm a redneck - Just look at my dogs.

Glenview289
June 11th, 2009, 01:07 PM
Rod,
That is how Brian and I measured the toe in when we did our car. I can't remember the source, but probably did a search on the site. We put straight edges against the center of the tire and parallel to the floor. We then measured the outside edges of the straight edge in the front and rear of the tire. The difference should be 1/16" total (smaller number in front-very important). If I remember correctly, we had a .005" shim under the front screw and a .012" shim under the rear screw that holds the bracket that mounts the lower hub carrier arm to the rear end. If you do the math, the .007" difference in shim thickness between the 2 screws that are approximately 7-8" apart would carry out to .030" on a 32" tire, or about 1/32" per side (1/16" overall). Be careful not to have the straight edge on an raised lettering you may have on the tire. You will have the same advantage that Brian and I had in that the body is not on the chassis. It will be much easier this way. Be sure to get the rear end lined up and locked down exactly parallel to the centerline of the chassis before setting the toe. I remember how great a freshly powder coated chassis looks. I'm sure Rick will remind you that this is the perfect time to put that first coat of wax on the chassis. If you need more info I can measure anything you may need on the car this weekend. Its over in Brians garage up on stands getting ready for a track day next week at Hallet Raceway in Tulsa.

Bill

RJacobsen
June 11th, 2009, 01:32 PM
Thanks guys, that helps clear it up. Back of tire to front of tire :doh:
with the Knock off adaptors off I can clamp a "tire sized" straight edge to each hub and not have to mess with the spongy side of a tire. having the body off is a big help. When waxing the frame do you rotate clockwise of counterclockwise? :confused:

RJacobsen
June 11th, 2009, 01:36 PM
Geary, I just went back and looked at your dog picture. Still laughing as I type. :D:D

diegokid
June 12th, 2009, 02:08 PM
Great picture, still laughing out loud.

Slither
June 14th, 2009, 02:00 AM
Diego,

Seems like I've seen those guys down here on the coast somewhere... no?






;););)




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