Expected camber settings

[Rottbott]

Thanks for the reassurance Nick. I'd like to get the rear right camber down to 1 degree to match the left though, for tyre wear if nothing else.

Correct me if I'm wrong, but as I understand it: The figure in millimetres is the difference in distance from the front of the tyre to the centre compared to the rear of the tyre to the centre. What that translates to in degrees/minutes of rotation therefore depends on the size of the tyres etc.

I have poly bushes everywhere except the rear control arms which I didn't get around to, they are still on old rubber.

[NickT]

Dan1986 Wrote:Thats a good link you've found there Ben.

Now how do we convert mm into degrees? NickT said the toe should be 3mm, but where is that 3mm measured?

The ange is measured from the wheel centre (discounting offsets!) to the edge of the rim.

Converting toe from mm to degrees:

Measure the rim diameter (usually in Inches) ie 17".
Convert to mm by multiplying the inches by 25.4
Divide the result by 2 to get the RADIUS in mm.

The toe angle is then the arcsin of the toe in mm divided by the radius.

When you increase the size of the wheel rim dimension, the toe angle in degrees is the same but the toe angle in mm has altered.

Multiply the result by PI to get the circumference.
Divide the result by 360 to get mm per degree.
Divide the toe mm by the mm/degree result to get toe in decimal degrees

In Excel the cell would be something like:

=DEGREES( ARCSIN( TOE_MM / ( (RIM_DIAMETER_INCH * 25.4)/2 )))

for decimal degrees.

This is why you will find that on most modern machinery the toe is expressed in Degrees and not mm. This will then not be dependant on the rim diameter if someone has changed the wheels for aftermarket ones (assuming the same tyre radius and circumference)

Someone has done a toe in calculator in Excell for degrees minutes seconds in:

http://www.fiatforum.com/miscellaneous- ... lator.html

Hope this helps.

NickT

[NickT]

Rottbott Wrote:Thanks for the reassurance Nick. I'd like to get the rear right camber down to 1 degree to match the left though, for tyre wear if nothing else.

Correct me if I'm wrong, but as I understand it: The figure in millimetres is the difference in distance from the front of the tyre to the centre compared to the rear of the tyre to the centre. What that translates to in degrees/minutes of rotation therefore depends on the size of the tyres etc.

I have poly bushes everywhere except the rear control arms which I didn't get around to, they are still on old rubber.

As per response to Dan wrt where you measure the toe from.

As the toe is changed at the front of the trailing arm this will induce an arc in both the vertical and horizontal planes at the rear tyre. I think once you have corrected the rear left toe, the camber will change to within spec too.

I had my car down at

http://www.wheels-inmotion.co.uk

centre when it first opened (as I was invited down by Tony) and had chance to play with thier kit for an afternoon. (Drool !)
Using real-time data I removed and then added shims to see what the effect was.
The camber went out but corrected once the toe was corrected again.

If it doesn't work out on yours you could buy the adjustable arms and then sell one of them. You would only need to correct 1 to the other. to get equal camber unless you plan to have fully modified rear suspension with adjustable ride heights etc.

I would change the rubber to new oem rubber as in my opinion you would need compliance in this part as the trailing arm moves on an arc (hence the bending of the oem trailing arm bolts). I would be interested to see how long the polybushes on the trailing arms last !!!!!

If it drives straight without any pull, brakes in a straight line, doesn't have different tyre wear patterns then I would be happy with it.

NickT.

[Dan6457]

Here is the before and after printouts from my alignment. You can see my camber is out of spec on the back too. Also the castor is out on the front too. Hopfuly once my chassis is finished it will be in spec as the old sway-bar bushes were shot which won't help it.

[NickT]

Looks like a nice readout that dan.

You can get the caster a bit closer by putting different thickness washers on the upper control arms/ anti roll bar ends but it would be such a faff.

Rear wheel alignment is spot on, NICE

NickT.

[Dan6457]

It was spot on. My car currently has no suspension bushes at all and no chassis

I might see if I can get the castor in spec, or at least the same both sides when I rebuild it

To get that rear tow in spec it took 4 shims on one side and 1 on the other!! Pretty thick shims too.

[NickT]

Dammit, I have re-checked my camber settings and they are about +60 degrees out!!!!!!!!



Only messing.......

NickT

[bozzzydmc]

Ha Ha !

The book settings are for pre 1985 model DeLoreans only...

You must be getting some serious tyre wear there matey!

[NickT]

bozzzydmc Wrote:Ha Ha !

The book settings are for pre 1985 model DeLoreans only...

You must be getting some serious tyre wear there matey!

Not really Mike as it is flying !!!!! Ha ha......

Nick-needsabeer-T

[Dan6457]

Hahahaha classic :lol:

That scene in BTTF is terrible isn't, how bad that mockup is!