Cup II Wheel offset advice - need 1 spacer

[mrdol]

I have an 87 911 Cab with 17x9 Cup 2 wheels in the rear. The offset marker says ET 15. My better half decided to attack a yield sign and small curb, this 10 minutes after I just replaced the wheel bearings and CV joints and parking brakes. The wheel was center bent from the hit and needed to be replaced. The one I found on Ebay and which now has my tire on it does not fit. Arghhh. The marking on that wheel is ET 47.

I want to use the new ET 47 wheel I now have as they seem hard to find. What wheel spacer should I use? I see that there are 1, 1.5 and 2" spacers available. Based on my measurements I need a 1.5" spacer for that wheel.

This car is not tracked and is a daily driver for us. Will there be any discernable handing differences if one wheel has a different offset?

BTW does anyone have one spacer they need to get rid of that would work? In have already found a pair of 1.5 and 1" adapters for sale if there are no offers.

thanks
eric

[KTL]

If you can score some factory 930 spacers? I think it will suit you perfectly.

I have 930 rear spacers on my car to fit some 911 Turbo offset ET 28 front wheels to the rear of my car. Most people call the factory 930 spacers "1 inch" size. I believe I measured the spacer to be 28 or 29 mm.

Your ET 47 wheel using a 930 spacer thickness of 29 or 28 (whatever it is) gets you to ET 16 or 15. That's close enough in my book!

One drawback to using the 930 spacer is that it's a slip-on spacer and not a bolt-on spacer. So you'll need longer wheel studs to be able to use the 930 spacer. I can provide pictures if you're not sure what I mean.

[mrdol]

Does the ET "X" represent the offset in "X" mm?

To get longer wheel studs it would appear that I would need to remove the hub and replace the studs in the hub.

Thanks
Eric

[Spede]

What you need is one of these wheel adapters...

http://www.boothedesign.com/spacers.html

[KTL]

Originally posted by mrdol
Does the ET "X" represent the offset in "X" mm?

That's correct. ET 15 = offset of +15mm

To get longer wheel studs it would appear that I would need to remove the hub and replace the studs in the hub.

That's correct. You knock the short studs out with a heavy hammer and brass rod, draw the new studs in with a steel lug nut and some concentric spacers. The cost of studs plus 930 spacer is probably about the same as the cost of a Boothe spacer. I don't like the bolt-on spacers myself, but they are a much quicker solution than replacing studs.

[widgeon13]

What does (ET) stand for in the ET 15 or ET 47?

[buster73]

Originally posted by widgeon13
What does (ET) stand for in the ET 15 or ET 47?

ET = Einpresstiefe = German for offset. The difference between ET15 and ET47 would be 32 mm which is close to 1 1/4".