Exotic_Car_Guy

I have been researching all the Rennlist member threads on the topic of 928 Wheel/Tire combos, and I'm still a bit confused with all the combos you'all have.

I am considering the following wheel dimensions for my car:

rear: 18x10 ET45
front 18x8.5 ET45
Bolt spacing 5x130

and tires:
rear: 265/35/18
front: 255/40/18

My car is stock and I would prefer not to roll the fenders or use spacers. I want to go as wide as possible, but don't want protrusion beyond the fenders and don't want any rubbing.

Does this combo sound like it will work for my 928S?

Thanks,
Gil

76FJ55

Don't think those fronts will fit from everything I'v seen/read the minimum front offset usable with our frender mods is 50 to 52 depending on tires.

hopwood

Will fit but not work. You need 7-8 inch fronts with offset of 60-65. The rear is different, whatever fits works.

Lots of people on here have fronts that fit but eliminate the negative scrub radius which makes the steering less stable when the wheels are on surfaces with differing grip (eg you put a front wheel on gravel or grass at speed). They will tell you their wheels work fine but personally i would never run anything but 60-65 front offsets on the 928. No car ever left the porsche factory with wheels that werent like this.

Joel

bigmac

Watch out that the rear tires clear the fender, I have about 1/8 inch clearance with 275/17 on mine .
Andrew Olsen has a lot of info on this.
Good luck

Exotic_Car_Guy

My thanks for everyone's feedback.

Can I get it right if I add spacers in the front with these 18x8.5 ET45 wheels? How do spacers affect the handling?

Gil
'85 928S, 5sp

FBIII

Spacers will make your front situation worse. The wheel needs to move in not out.

Mrmerlin

Gil for the front you want a number no less than ET50.

adding a spacer will decrease the ET number.
so if you add a spacer thats 15 mm and had a wheel with an ET of 50 ,
then it would become an effective ET of 35.
For the rears 43 ET of the wheel is about the max you can go with no spacers.
Note ET 65 is stock.
If you had a wheel with an ET of 60 you could add a 15mm spacer to move the wheel out towards the fender for and effective ET of 45

pcar928fan

Some of the best fitting 18" wheels out there right now that are pretty easy to find and pretty affordable most of the time as well are the CIII (or Carrera III) wheels. I prefer the '02 - '04 (and maybe later even) 996 Carrera Lightweight wheel personally, but the fitment is not as tidy...the fronts are a 50ET offset and stick out a little far, the CIII's are a 57 offset I think and work like a DREAM on 928's!

Exotic_Car_Guy

Thanks guys for educating me (I was visualizing the offset backwards). I guess I'm going to have to find different wheels.

Any recommendations for cost effective sources for 18" wheels for the 928? Below are some of the options I'm considering.

Gil
'85 928S

IrishLegend

I like A, B & H. Not in that order.

Jon B.

Good luck with "I"! I don't think Kinesis will make that for you any longer. The only set I have seen in on DR's euro and they are 19s if I remember correctly.

pcar928fan

Any wheel 3 piece or otherwise that has all those bumps or actual bolts on the outside around the perimeter are going to be HELL to clean!! I mean, SERIOUSLY, they are going to be TERRIBLE to have to clean.

I like that Cayman wheel pretty well, and if I recall correctly they are a good offset too...

A is a 19" wheel
B is a 17" wheel (and one of my fav factory 928 wheels I might add!)

Exotic_Car_Guy

How about these wheel dimensions for fit on my 85 928S?
rear: 18x10 ET58
front 18x8 ET56

Gil

Kevin B

Yes they will work your 85 comes with a factory 21mm rear spacer with it removed a 285/35/18 will fit. Up front 235/40/18 depending on the tire. There can be up to a 1/2" differance in over all tire width between tires with the same tread width. Also 225/40 & 235/40 isn't much side wall height for these heavy cars, there are some 225/45/18 tires out there. The Panamera will offer more options in the future with a 60mm front off set, clones are sure to follow.

Exotic_Car_Guy

Kevin,
Very helpful.
Thanks,
Gil