targatime

I am going to be buying a set of wheels off a 93 964 coupe "Jonesey's car" The wheels have perfect fitment on that car.

My car is a stock 90 targa with 16" D90 wheels.

The new wheels and tires will be a bit wider...I believe they are 7.5" on the front and 9" on the back they are also 17".


I've read conflicting articles...some say I'll need to go to 10 mm steering stops from the standard 6mm, and possibly have to do some modification to the wheel wells...other articles say that nothing has to be done so long as the offset works (which it should if they fit on the 93) and they are not 18"s.

Can anyone set me straight here???

PC2

It depends on the offset of the wheel and size and brand of tire your putting on. I have 7.5 front with 205s and 9 rear with 255s. Neither the front or rear are rubbing.

joey bagadonuts

The original 964 front wheels were 6 x 16. From 92-on, there was an option for 7 x 17 fronts. On the earlier cars, the steering radius was set up to work with the narrower wheels but needed to be adjusted to accommodate the 7s.

Now here's the tricky part. Even though they both use 205 tread widths, the overall width of such tires increases when mounted on wider wheels. That's why there's a clearance issue.

ian c - u.k

didnt porsche fit different stops on the later cars that had 17's as an option ??
to reduce the ammount of lock , to stop the tyres clashing with the inner wings/tub ??

targatime

My rims are the AT Italia Razze 5. The fronts will actually be 7's not 7.5's...would I need stops then with the slightly narrower tire?

ian c - u.k

my c2 had 7x17 and 8x17 factory .
been told mine will have limiters , but i'm not sure

i think this part may be what joey was refering to

ian c - u.k

964 347 325 02

joey bagadonuts

Every car is different so the only way to determine whether you need stops is to buy the wheels, mount them on your car and give it a go. Keep in mind, we're talking about some slight rubbing at full lock. You'll feel it when pulling into tight parking spots. Ideally, you'd want remedy this issue with the proper Factory fix but it isn't fatal.

I believe it's part #17 in the diagram. Basically, you replace the current spacer with a thicker one to reduce the steering range.

targatime

really appreciate the input and advice...thanks

Jeff Curtis

Targatime, my two cents:

Install the wheels/tires, go for a drive and in a parking lot somewhere go to full lock, right, then left, just for a second...drive home, take off the fronts and see if you had some slight rubbing...if not, try a higher speed full lock, right, then left, if you still don't have rubbing, you're likely in the clear.

This test will ensure minimal rub marks on your inner fenderwells.

If you have slight rubbing, try a 3mm wheel spacer (no larger w/factory lug nuts!!) and that should clear any troubles up with clearance. The next time you have steering rack/tie-rod maintenance done you can address the 10mm steering stops issue.

targatime

I'll do the test and let everyone know...thanks again!

WMRiceman

Jeff, you mentioned putting 3mm spacers in. Where did you get the 3mm ones? The thinnest I've found are 6.5 mm through Performance Products. I just put on some Kumo VRs and I’ve got 225/45/17's in the front and I also want to avoid rubbing. I bought a couple of the 6.5mm spacers but now I'm stuck with changing wheels studs to longer ones to make them work, which I don't want to do. I’d much rather use 3mm spacers and keep the factory wheel studs.

targatime

I believe you're confusing steering stops (small shims that keep the wheels from being turned so far the tire can rub the wheel well) with spacers...which make fill up the "gap" that would occur if the offset was too great in the rim.