The rear flange-to-flange width on a 1200 is 5mm wider than the flange-to-flange width at the front on a disc-brake 1200.

And a 7" wheel does not have the same clearance as a 8" wheel. Many 7s will fit, but most 8s won't. It depends on the specific offset.

god this stuff is confusing!.. let me build an engine any day!! haha

BUT i do get it, the overall width of a 7" rim is around 8" and the 8" is approx 9".
This is the where the backspacing is measured

The offset is measured either + or - from the centre of where the tyre meets the rim.

So in conclusion my diff isnt shortened enough to use any of the wheels that i want! which is a major problem! And in short i am not very happy about it.

EDIT- Cheers Ben for taking the time to measure her up for me!

my 7.5s are exactly 8.0inches in width.

Yes the wheels I measured are 1/2 inch wider than the nominal size.

yeh so a general rule of thumb is 1/2 to 1" more then the specified width..

well... i might just buy the wheels that i want, in the offset that i want.. most probably 7's and go from there.

I may be looking at doing a deal with someone that has an uncut R31 diff housing!.. a good deal at that!

I tried the wheels off the back of my dads panel van, 15x8, 3 3/8" Backspace and 205/50-15 tyres
I was suprised that they fit! my diff needs to be shortened a further 50mm approx each side for them to fit but it will happan!

And considering i could get prob another 20mm clearance when i roll the guards (they are untouched atm)








Make the car fit the wheels i say! haha

haha yeah they will fit fine, as long as the car doesnt move in relation to the wheel at all

as soon as you turn any kinda corner that will make the car even think about leaning over in the slightest the tyre will rub

yeh thats what i thought also, these wheels wont be used on the road, ill be getting a set of 7's for road duties. So if these rub a bit i dont really mind, as long as it doesnt slow me down lol