Porsche Enthusiasts Club Forum

I've got a 1988 924S and i've been offered some Boxster wheels.

They are:
Fronts - offset ET55 - 7J tyres 205/50/17
Rears - offset ET50 - 8.5J - tyres 255/40/17

Will they fit?
Will I need spacers?
Will it affect the gearing/speedo readings?

Kelvin.

You can use this http://www.miata.net/garage/tirecalc.html to look at the new vs old sizes.

No won't fit without big spacers, of around 30mm which will be A. expensive & B. not do the geometry or wheel bearings any good. You need early 944 wheels for this of around ET20-30

I think that what Im going to say contradicts other posts here, however... Based on my experience the only Boxster rims that will fit are the original 6" & 7" x 16" wheels. The rear 7" rim fills the available space completely so you simply wont be able to fit an 8.5" rim (these have an offset of 40mm, so in real terms the 8.5" rims will be the best part of one inch wider still). Talk of spacers is mistaken; spacers can only increase the offset obviously, not reduce it. As is the reference to early 944s: the 924S uses the same offset as series two 944s (52mm).

Im rushing too much... The fronts will fit: the Le Mans limited edition used the 7" ATS rims off the series two 944. Not much use on their own though.

Simon

Err spacers can reduce the offset dependant on whether the offset is positive or negative. A negative offset like what later pork wheels are with a spacer reduces by the size of the spacer, so ET55 with a 30mm spacer is ET35, assuming you have clearance for the offset rim of course!
Linky is here:-
http://coolcarrims.com/wp-content/uploa ... raph11.gif

Spacers can only help where the hub doesnt stick out far enough, for example where you want to fit new wheels to a pre-ABS offset car. In this instance the car has the later 52mm offset (meaning that the hubs stick out far enough already). The reason that the wheels wont fit is because theyre too wide, even though the offset is broadly correct.

As I mentioned in my first rushed post: the 924S uses the later offset, not the 23mm offset of the earlier cars,

Simon