Camber effect on wheel offset

[Impureclient]

I know there's probably a simple math equation for this but I'm not finding it in a search and too tired to figure it out.
When you go from 0 degrees camber to -1, how much does that move the wheel each degree or even better, the edge of the tire on our normal size tires?
I know each tire will be different depending on how tall it is but just figuring a stock wheel and tire if that make it easier.
Specifically, I'm trying to figure out how much a 225/45/17 on 8" wide wheel moves inward going from 0 camber to -2.
I think it's around 2 or 3mm but I'm trying to dial it in perfect for spacers.

[Spuds]

Using bolts or plates? I mean, the difference is likely small, but there is a difference.

[Impureclient]

Originally Posted by Spuds

Using bolts or plates? I mean, the difference is likely small, but there is a difference.

It was Whiteline bolts. I think this: http://www.pagetutor.com/trigcalc/trig.html
will work to figure this out but I don't know what numbers to plug in where. Tire height is 635mm.

[Spuds]

1 degree of camber is 5.51mm by my calculation.

2 degrees is 11.03mm.


Sohcahtoa bro!

[Impureclient]

Originally Posted by Spuds

1 degree of camber is 5.51mm by my calculation.

2 degrees is 11.03mm.


Sohcahtoa bro!

So the tire moved at the top 11mm inwards? That seems like a lot. Did you use that link I put up and if so which figures did you use or did you figure it out on your own?

[Spuds]

Originally Posted by Impureclient

So the tire moved at the top 11mm inwards? That seems like a lot. Did you use that link I put up and if so which figures did you use or did you figure it out on your own?

Yes. It does seem like a lot, but that's what the math says. Plus, remember that 10mm is 1cm. Really not a lot considering the hypotenuse is over 30cm and you are at the very top of the arc.

Now, there's a few assumptions made easier by your camber bolt choice. This assumes the center point of the outside of the wheel does not move laterally, which will cause the calculations to be off by whatever amount you move it using the bolt, assuming only one is eccentric. If both are eccentric it will even out.

I don't need a fancy calculator to do basic trigonometry. Here's the formula:

sin('camber')*('rollingRadius')='topLateralMovemen t'

sin(1deg)*(.632m/2)=.00551m=5.51mm


Edit, if you don't believe me, C is 316 (half of diameter) and X is 1 in that calculator you sent me. A is your answer, and if you subtract B from C you get the increase in vertical fender gap, though the gap increase is likely offset by the vertical motion caused by the spindle and wheel width moving the wheel center upwards relative to the fender.

[Impureclient]

It doesn't seem to make sense. I had a 7.5"(45mm) wheel on there with 0 camber and now have the 8"(35mm) wheel with about -1.8 camber and I added a 5mm spacer. It looks like it's a little more sunken in now.
I guess the pivot point isn't exactly the center of the wheel and that's why this doesn't seem to add up with 11mm. According to that 11mm, I would have to add a 15mm spacer to get it to look the same
as it was with the old wheel. It looks like it needs about 3mm more to get there with the 5mm spacer I have. Which means I would need a 8mm spacer to be close to what it was.

I forgot all the math I learned 24 years ago and now width x length is about the hardest math used lately.

[Spuds]

Originally Posted by Impureclient

It doesn't seem to make sense. I had a 7.5"(45mm) wheel on there with 0 camber and now have the 8"(35mm) wheel with about -1.8 camber and I added a 5mm spacer. It looks like it's a little more sunken in now.
I guess the pivot point isn't exactly the center of the wheel and that's why this doesn't seem to add up with 11mm. According to that 11mm, I would have to add a 15mm spacer to get it to look the same
as it was with the old wheel. It looks like it needs about 3mm more to get there with the 5mm spacer I have. Which means I would need a 8mm spacer to be close to what it was.

I forgot all the math I learned 24 years ago and now width x length is about the hardest math used lately.

Are those mm values on the wheels straoght offset specs? If so, I think you are looking at a total of about 13.5mm without considering any tire differences. The tire on the wider wheel is likely part of the difference.

Lol I'm an engineer and I have to come on an internet forum to solve any problems using math. Give it a few years and I'm sure I'll forget too.

[Impureclient]

Originally Posted by Spuds

Are those mm values on the wheels straoght offset specs? If so, I think you are looking at a total of about 13.5mm without considering any tire differences. The tire on the wider wheel is likely part of the difference.

Lol I'm an engineer and I have to come on an internet forum to solve any problems using math. Give it a few years and I'm sure I'll forget too.

Yes the mm values are the offset. I forgot to add the front had 20mm spacer and rear had a 25mm one which made the offset 25 in front and 20 in rear.