dan davies

Warning - 18inch wheels are not supported on the Porsche 928
Retrofitting 18in wheels on Porsche vehicles which do not have 18in wheels as original equipment is NOT ALLOWED in main dealers. "Endurance tests have shown that equipping certain Porsche vehicles with 18” wheels in an application not already approved by Porsche Cars may result in loosened bolts and /or threaded connections, on the front wheel carriers. This, in turn, may cause fractures in these components. Fractures may also occur in the front strut mounts and in the body in the area of the rear suspension as a result of the installation of 18in wheel not already approved for installation for this specific application.
Such damage can occur without warning and the vehicle may become very hard to control or steer as a result of this Improper installation."

Source: Technical bulletin 9305


Offset
This is the difference between the centre of the wheel and the position of the hub within the wheel.. The spacing requirements of a 928 are unique - you cannot take wheels off a 911 or 944 and bolt them straight onto a 928. If the spacing is out then the wheel and tyres will contact the bodywork over extreme bumps or when turning causing expensive bodywork and tyre damage. In this scenario you will need to fit spacers and these can cost around £400 alone, so beware. When buying wheels make it clear they are to be fitted to a 928. If buying from a reputable supplier they should be supplied with the correct spacing built into the wheels so just they can be bolted straight onto the car.

Randy V

That's obsolete info, Dan.

heinrich

Better get our forum sponsor, Dave Roberts (see above for his ad) to immediately remove his 19-inch wheels from his 928 and stop selling them then

heinrich

Wait a minute ..... ED, GOOD TO HAVE YOU BACK

Richard S

Good one Heinrich (Rennlist oldtimers will get this one)


Rich

928ntslow

They are now...AND, technology has allowed us too!

This statement makes no reference to the 928. Besides, at best, that was 1995.

The 928 is a tank! Ask any racers if this has ever happened with their 928's while they ran 18in.They run them HARD TOO....not to mention all the folks running them on street cars. There are going to be A LOT of folks to ask however.

This bulletin does not apply to me...I am running 19in


This subject has been discussed to death! The 928 community has cracked the code years ago.

Dan, please do not take what I say as an attack by any means. I have no idea how new you are to the community or even 928's. Rest assured though, the 928 legacy has been left in our hands and we as a community , have taken the car further (and better in some cases) than Porsche ever intended.

Wheels have been tested and tested and tested by 928er's. I cannot think of one incident of all 928's worldwide running larger than 17in that has caused any issues that I am aware of. If anyone else has better info, please correct me.

greg928GTS

I really like the look of the wheel taking up more of the wheel well.

Is your ride height lowered at all?

AO

The only issue that I know of is the potential of bending the rims if you hit a pot hole, but that's more of a function of the wheel than of the car. I wonder who will be the first to put 20's on their 928?? j/k

BTW, H, that was a good one. It did remind me of long lost Ed.
YMMV

928ntslow

Ed was actually pointed out to me when I showed up at the Frenzy this year! Andrew, you should have seen him cause you were there!

Greg, my car WAS lowered for a long time. I just had the ride height raised to near spec after putting these wheels on. I raised it up about an inch and the bottoming out and scraping is near gone! So to directly answer your question, I would have to say no.

John Veninger

Actually I think Dan is correct. Porsche never officially "approved" 18" wheels on a 928. The main reason was that they never tested them since the car was discontinued.
As was stated, many have run 18" wheels without issue.

YMMV

Randy V

Hilarious, H!