Wheels are the one thing that confuse me. My brain doesn't have the capacity for the math needed to make sure that wheels work. Once people start talking about tire size and offset and whatnot my grape shuts down.

Local seller has a set of BBS Montreal in this size: Rear 20x10 inch with 285/30/20 tires. Front 20x9 inch with 255/35/20 tires.

Ad states that they will work on 2003-2006 XK8. Mine is a 1999 XK8.

I have coilovers, so can adjust for height if necessary.

But I don't know why these would work on a 2003+ XK8 and not a 1999 XK8. What changed for those years?

Before engaging with the seller and wasting time figured I'd ask the experts.

Yes I know that the 20" may give a more harsh ride.

Currently mine has 17" Revolvers.

 

They will bolt on and have a more aggressive offset. Since you have coilovers and are presumably lowered, they will make the stance more aggressive. You may have to raise the car depending on what size tire you are currently running and how low your ride height is set.

 

I have a 1998 XK8 that the PO replaced the 17" standard wheels with 18" ARIS Double Sevens.(16" STARBURST will fit 'minimum')
16" wheels will NOT fit my 2000 XKRs. I have not tried to fit 17" to the XKR.

All X100s use 5 on 4 3/4" wheels and the offset should be the same for the suspension 1997 to 2006.
Brake caliper/rotor differences are the main reason for larger wheels on later or supercharged cars.

 

Thanks.

I contacted the seller and he says he was told by someone who had a 98 XK8 that "the 255/35/20 tires on the front may rub when bottoming out and may rub slightly on a full turning circle if the suspension is not perfect". The fronts are 9" on the Montreals. I do have the coilovers so can raise the front and rears to accommodate somewhat, but I also don't want a large gap in the wheel arch, which is the one thing I'm not a fan of (hence getting coilovers to lower the car about an inch or so).

If I have to raise the car to accommodate 9" wide fronts then it would really defeat the purpose. The Montreals look really sharp - better than chrome revolvers but don't want to trade one issue for another.

I do like how the 10" rears on the Montreals fill out the back of the car

 

I went with 20" Sepang's on my 2002 XKR. The tire sizes are 255 35 20 on the front and 285 30 20 at the rear. Nothing rubs in my case, I guess quite a bit of it depends on the individual car. In fact, I ended up buying the shorter springs so that I could lower my rear end a little bit. For some reason after the wheel change, it seemed like the rear end was sitting too high. I also added the rubberized black Fender extensions that apparently came with the larger wheel option from the factory.

 

The change in ride height will likely be minimal (if any) since the tire difference will be significant to offset wheel size.