I am running 225/40-ZR16 Dunlop SP-8000's on both my '92 GTI 16V, and my
(former - estranged wife has it) '97 GTI VR6.   Both cars have BBS RC's,
16x7.5" and a 35mm negative offset.
I have virtually no rubbing problems with the '92, except with a lot of
extra weight in the back and when hitting really nasty dips/bumps at speed.
It has NS Sport Lowering springs/Boge ProGas inserts/shocks, and NS 25/28mm
bars and F/R NS stress bars, so it's pretty tight.
The '97, with NS Sport Lowering springs and Spax adjustables, NS 25/28mm
bars and front NS stress bar would rub occasionally on big dips/bumps, and
more often with extra weight in the rear.  I switched to Ground Control coil
overs on the Spax, with 325in/lb front, and 225 in/lb rear springs, and it
was about the same, with the ride height set the same as with the NS
springs.  I decided that the car was a little too stiff, and changed the
springs to 300/200, and the rubbing got pretty bad, again at the same ride
height as the NS setup.  I was planning on swapping the 225 rear springs
back in, but then the marital problems started, so I never got around to it.
The bottom line is, that depending on your exact wheel offset, suspension
setup, and ride height, you will probably experience some degree of contact
in the rear with the 225/40's.  I personally love those tires, so I would
work around it with spring/shock rates, ride height, and probably rolling
the rear fender lips, before I'd give up.  Also, the degree of contact at
it's worst on the '97 barely left marks on the tire sidewall, so it's not
dangerous, at least.  And on the '92, it doesn't even leave a mark at all,
but then, as I said, it rarely ever touches, anyway.
Oh, and note that tires of the same size by tire different tire
manufacturers, can/will be slightly larger/smaller.  I know that the Toyo
Proxes T1's in 225/40-ZR16 are slightly wider, at least at the sidewall
where the rubbing occurs, which means that they rub noticeably more than the
Dunlop SP-8000's that I run.
Questions?  Please keep them brief, I'm tired of typing...:-)

-Holland
hjppacbell
Woodland Hills, California

>Are you running the 225/40's? Any clearance problems?

It depends on your wheels' offset and how low you go with the coilovers.
I've got 225/40/16 Dunlop SP9000's on 16X7.5" BBS RC's, and I'm lowered
nicely with H&R coilovers. (two finger gap) I use 5mm spacers in the rear
only to clear the coilovers.  Absolutely zero rubbing, anywhere.  I've even
done track events with 'em.  The wheel offset is the key, the RC's are just
perfect - 35mm ET.

Rob Baldwin
'98 GTI VR6
'86 GTI Hybrid