Wheel offset and backsizing (spacing)...

Great info - You need to post that to the Knowledge Base so it doesn't get lost.

I'd like same for the various 4 lug wheels that fit stock drums/disc.

As the famous bar philosopher, Jimmy Buffett, said "Grow older, not up"

Damn!  I so wish I could weld like that guy!  (Or even half as well as my son!)

Terrific chart, Al.  Already stashed a copy in my files.......Thanks.

Yeah, Gordon, the guy's metalworking skills are killer! I've seen a plastic Speedster widened at the back; the guy cut the rear fenders (about 1" away from the lip all the way around) from the top front of the fender all the way back, and then spaced it the same way ( progressively wider as you moved to the back of the fenderwell). The car had 16x8 Fuchs alloys and 225/50x16 tires on it and after it was finished I couldn't initially tell the work had been done. The guy who did it said it was more work than he figured (I think there was way more work toward the back of the fender to somewhat keep the body shape and not look "flared") and would do it differently if called on to do another one. I think this way would be easier to retain the stock lines (so the car doesn't look modified). When a wheel/tire combo like this is used, the top of the suspension snubber may have to be cut back a little and button head/allen key springplate bolts may be needed to clear the sidewall of the tire. Al 

Thanks for sharing that chart, Al! Great info. I learn something new every time I visit this site! 

Note- There are 2 different part #'s for the 16x6" factory Fuchs alloy- 911.361.020.43 (listed as "early") and 911.362.113.00 (late). According to the Porsche wheel weights chart (I think I've given the link for this before but here it is again so it' all in one place)- http://members.rennlist.com/911pcars/WheelWts.html the backspacing and offset are the same. There are 3 different part #'s for the 16x7" wheel- 911.361.020.44 (early, '77-'84), 911.362.115.00 (late, '85 on), and 951.362.115.00. The 911 numbered wheels have the same offset and backspacing, while the 951 wheel has 138mm backspacing and is found (I believe) on the fronts of 944's. The 2 different versions of the 16x8 (911, 951 part #'s) are in the chart above.

There is also a 15x11" wheel listed- 911.361.020.05 with no backspace or offset info available.

Very nice chart Al. Thank you. I have 7s and 8s, with the 41 and 42 on the end. Not R wheels, but will fit very nice on the '72