Quick wheel offset question... thks

[TC3]

I can't remember if you would.....
add a 18 mm spacer to 20 mm wheel to fit a 38 mm offset car?
Eg: an E-34 wheel onto an E-36 car
OR
add a 18 mm spacer to 38 mm wheel to fit a 20 mm offset car?
Eg: An E-36 wheel to an E-34 car.

Also these would be BMW offsets, so I'm not sure if they would be a neg or pos offset.

Thanks for any help
.:

[EDDINANM3]

The reason 20mm offset wheels won't work with the spacer on a E-36 is because the offset is already to much to the outside and the rear will rub, so by putting on the spacer your moving it further outside which doesn't help. You need a wheel with a 45-50mm offset and then get a spacer up front, the back will probably be ok, this is how you can run 8.5 and 9" rims on E-36's. The higher the number of offset the more the rim will be towards the inside of the car. So while a 20mm offset from a 5 series might work in the front it won't work in the rear on a E-36. There is a lot of room towards the inside on the rear of the E-36, but the front is the opposite all the room is on the outside of the wheel well. Remember that and you won't have any problems.

[TC3]

So then could you have a 20mm offset wheel machined down to a 38mm offset on a 8.5" wide wheel? Would it then fit on an E-36 BMW?
:
Thanks for the reply

[EDDINANM3]

The 20mm offset on a 8.5" rim might work in the front, but it will be sticking out from the fender well a bit, however the 20mm offset won't work on the rear because its already to much to the outside of the fender well. To make 8.5" rims work right you need a 38-42mm offset. My SSR Comp's were 44mm offset and the rear was fine, but the front rubbed so I got some 15mm spacers and that solved that.

[TC3]

Thanks for the info, I get it now.
Curious.... is it a common thing to have a wheel machined down from the inside to change the 20mm offset to a 44mm?? Is it safe?? Also, In your opinion, a 29mm offset is ideal for the front on a 8.5 wide rim?!?

[Mode]

Originally posted by TC3
Thanks for the info, I get it now.
Curious.... is it a common thing to have a wheel machined down from the inside to change the 20mm offset to a 44mm?? Is it safe?? Also, In your opinion, a 29mm offset is ideal for the front on a 8.5 wide rim?!?

I don't think that is too common. Cobbing 14mm out of the back face of the wheel will considerably weaken the wheel.

My 18x8.5 wheels have an offset of 41mm (f + r).