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Smoothie

Checking the rear wheel camber today with my fancy aluminium caster/camber gauge, it occured to me that you should be able to do it with just a plain ol' framing square + some math. Here it is -

What you need - a good sized framing square like 24" x 16", a ruler, a pen, a flat surface to park on that's all in one plane (doesn't have to be perfectly level, but does have to be flat (in one plane)), and a calculator with "tanˉ¹" function (aka- inverse tan).

1) Place the 24" edge of the framing square straight up-and-down against the tire either in front of or behind the contact bulge. If camber's negative which it should be, the framing square will touch the tire sidewall at bottom, but not at the top - this as the 16" side of the framing square rests on and parallel to the floor and sticks out perpendicular to the side of the wheel, tire and side of the car.
2) Locate the center of the contact point between tire sidewall and framing square at the bottom and put a thin horizontal mark on the tire there. Then tilt the framing square so it touches the sidewall at top also, and put another small horizontal mark at the center of that contact point. Then tilt the framing square back so it's again resting parallel to/on the floor and touching the lower sidewall contact point.
3) Measure the distance between framing square edge and sidewall at the top mark. Call that "A".
4) Measure the distance between the bottom and top marks. Call that "B".
5) With your calculator set to degrees, calculate A divided by B, then hit "=", then hit "tanˉ¹". The result will be your camber in degrees.
_________________
"..it's made in Germany. You know the Germans always make good stuff."

'82 924T, US version, dark green metallic, 5 speed Audi 016G gearbox

emoore924 · Joined: 13 Apr 2004 Posts: 2822

I think you have waaaayyy too much time on your hands. Is there like 4 feet of snow on the ground where you are or something?

Good info. Thanks.

Smoothie · Posted: Thu Mar 24, 2005 2:59 am Post subject:

No snow...just the intoxicating scent of freshly delivered tires -

Check this one out...it was caught in time, but looks like it had some nasty plans for me -

I won't say who made that tire, but can say it ends with "oodrich".

_________________
"..it's made in Germany. You know the Germans always make good stuff."

'82 924T, US version, dark green metallic, 5 speed Audi 016G gearbox

emoore924 · Joined: 13 Apr 2004 Posts: 2822

Oooooooooo

Ewwwwwww

That BFG has "catastrophic failure" written all over it. Looks like an *old* tire too. What's the date of manufacture? (the 3 or 4 numbers in a little oval on the sidewall something like 027 or 0417).

Smoothie · Posted: Thu Mar 24, 2005 9:29 am Post subject:

That was a BFG g-Force T/A KDWS 205/55r16.
The date code was "2 4 00". They were removed this past December. Not too too old, but that one was from the side that got the sun all day - maybe that's a factor in the aged look.
_________________
"..it's made in Germany. You know the Germans always make good stuff."

'82 924T, US version, dark green metallic, 5 speed Audi 016G gearbox