I'm doing an alignment for s customer here at the shop, and he is asking for 1/8th toe out up front - how do I translate that into degress as measured by my Hunter alignemtn machine?

My machine will tell me +.0x or -.0x with x being a number, so I'm trying to get the equivalent of 1/8 toe out.

Thanks in advance.

 

search is your friend..

but here's the formula to convert:

toe in inches = (tan x) * tire diameter where x is the degrees..

if i remember my trig correctly, that would make:

toe in degrees = (tan^-1 (toe in inches/tire diameter))

the first part is right.. the second part(my math) may be wrong, someone correct me if it is..

on my car, it roughly works out to -.22 degrees total, 1/16th on each side is about -.11 on each side..

 

Thanks very much, that was quick.

Onto that alignment now, thanks.

 

https://honda-tech.com/zerothread?id=1061318

soh cah toa

EDIT: Google calculator to the rescue: Assume tires are 23.5" in diameter.
Google arcsin(.125/23.5) in degrees
You get arcsin(.125 / 23.5) = 0.304766222 degrees
http://www.google.com/search?s...grees

 

ITR forum > RR/AX forum.. I had searched a couple months ago and got my formula out of here..

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by mstewar &raquo;</TD></TR><TR><TD CLASS="quote">ITR forum &gt; RR/AX forum.. I had searched a couple months ago and got my formula out of here.. </TD></TR></TABLE>



Arctan vs. Arcsin give the same number for small angles... it just depends on if you put the right angle to the tire or the right angle to the centerline of the car (I used centerline of the car).

In this case the diff in arctan(.125/23.5) in degrees vs. arcsin(.125/23.5) in degrees is 0.3047619 vs. 0.30476622.

What did you use for tire diameter?

Anyhow, an eighth TOTAL toe out is .3 degrees, or .15 on each side. YMMV, IANAL. I asked an alignment shop for xyz degrees total toe out in front (even wrote it down for them) and they put xyz degrees on EACH SIDE. Bastards.

-Chris

 

I used 22 inches for my tire diameter..

I assume you're using different tires than I, hence the 1.5" difference..

 

Does the Hunter alignment machine not have the ability to display toe in inches? Last time I got mine done on a Hunter machine it did...

 

what 22" tire are you using? All the 205, 225 15's and such are just under 23" or taller.

 

it was on some very bald azenis.. and I'm sure there was a bit of error involved..

i'll actually be redoing the alignment tomorrow the old fashioned way(no machine) on my R compounds..

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by mstewar &raquo;</TD></TR><TR><TD CLASS="quote">it was on some very bald azenis.. and I'm sure there was a bit of error involved..

i'll actually be redoing the alignment tomorrow the old fashioned way(no machine) on my R compounds..</TD></TR></TABLE>
[threadjack]

Which old-fashioned way?

[/threadjack]

 

not using a machine..

plates and strings/measuring tapes

 

What would be really nice is if someone would do a flash card for this. Give a range of popular tire diameters and under that what each degree works out to be in inches.

Then RR/AX &gt; ITR Forum

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Todd00 &raquo;</TD></TR><TR><TD CLASS="quote">Then RR/AX &gt; ITR Forum </TD></TR></TABLE>

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Chris F &raquo;</TD></TR><TR><TD CLASS="quote">


</TD></TR></TABLE>

Nice

That's per side and not total, correct?

 

no 16" love?

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by trutuner &raquo;</TD></TR><TR><TD CLASS="quote">no 16" love?</TD></TR></TABLE>
I have 16" streets and snow tires. Never never again, tire selection sucks.

Just use 23" for 205/45R16, 23.5" for 215/45R16, 24" for 205/50R16

-Chris

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by trutuner &raquo;</TD></TR><TR><TD CLASS="quote">no 16" love?</TD></TR></TABLE>

Rim size does not matter. What you are looking for is overall *tire* diameter.