johnr265

Okay alignment gurus, I recently had an alignment and specified .15 degrees toe in per side. The shop said their machine measured in inches and the sheet came back and said:

"0,15" (note it is a comma, NOT a decimel point)

Is this .15 inches or 15 minutes and how does this convert to degrees. Looking at the archives, I found the following info:

"The formula is t = 2 * 18 * sin(a). t is inches total, a is angle per side"

and

"Factory rear spec is 13+/-2 minutes per side or about 0.18º to 0.25º per side"

and

"one minute = .0052 on a 18" wheel, 3/32 = 17.8 minutes of toe"

By all of this information, this suggests that I actually got .25 degrees per side. Is this correct? Thanks in advance.

-John

Yargk

15 minutes is .25 degrees, yes.

However, if it's in minutes it should read with a " somewhere. It would be like 0,15" .

johnr265

Oops, just realized how I typed it. Indeed, it said exactly that,

0,15"

so this is minutes, not inches? Thanks.

johnr265

If our presumption is correct, then in order to get .15 degrees per side, that would be 9 minutes per side? (.09425 total inches divided by .0052 then divided again by 2 to get per side).

It's much cheaper to get it right on paper before they put it on the rack.

Yargk

Exactly, you want nine minutes.

It's just a number base problem. For instance you could say I'll meet you .5 hours which is 30 minutes from now. You're getting the right answers with decimal conversion factors, but for me it's easier to think of such a calculation as .5 hours * (# of minutes in an hour = 60 ) = 30 minutes.

So .15 degrees * (# of minutes in a degree = 60) = 9 minutes.

It's definitely cheaper to work stuff out beforehand. I've learned the hard way that this rule applies to everything you'd do with a car.

LVDell

.15 degree (9 minutes) is 1.19mm.
.25 degree (15 minutes) would get you 2mm.

Personally, I run 2mm of toe IN per side in the rear and .5mm of toe OUT in the front.

johnr265

Yargk,

Makes perfect sense. Kind of like the SAT. There is always a shorter way to work out the problem. Just so I know, if the printout were in inches, would it have said

0.15"

with a decimal point instead of a comma?

I love this site BTW.

LVDell, sounds good. Right now, I am concentrating on AutoX but those are definitely great settings for the track.

LVDell

Remember, some people use a comma instead of a decimal. Depends on where they learned their math punctuation.

If you are interested in Auto-X setup contact Rad (NJ-GT) as he is a phenomenal Auto-X'er and has ALOT of experience with setup, etc.