problems with offset on cup wheels

kmhemi · 07-05-2005, 04:38 AM

I bought a set of 16 inch cup wheels for my 78 SC. They are 8-52 for the rear and 7-55 for the front. The rear looks like it will require a 3 or 3.5 inch spacer but the front looks like it will need spacers too. There is a factory spacer on the front already. What should I do sell them or use them ?? I don't mind buying spacers if it's ok to use them but I don't know what to do with the front.

Oh Haha · 07-05-2005, 06:14 AM

I have 1inch front and 2.25 inch in the rear with the same wheels.

mtelliott · 07-05-2005, 06:31 AM

The rear doesn't need 3 1/2 inch spacers. You need a spacer that equals the distance off the offset plus 1/2 inch (going from a 7" to an 8" rim). It's approximately 1 3/4 but get out a metric calc and do the math. Plus, I doubt your front has a spacer. You'll need a spacer that equals the distance plus the 1/2" for the bigger wheel.

I did the same thing and it took about 4 hours to change everything over (installing longer studs) plus about $400 in longer studs and spacers. It's not a cheap conversion.

Michael

Oh Haha · 07-05-2005, 06:44 AM

I spent about 400.00 on my spacers from Boothe. I ordered the wrong sizes twice. Duh!! At the time I didn't know about this forum. For what I spent on wheels and spacers, I could have purchased a set of Fuchs 7+9's. Live and learn, I guess. Post an add here for spacers if you plan on using the wheels. You can save a lot of money on them, I 'm sure.

kmhemi · 07-05-2005, 06:53 AM

Are your wheels the same offset as mine ?? If they are then I can just order what you have and be done with it. Mine are 964 wheels.

Oh Haha · 07-05-2005, 07:12 AM

Your rears are 8 inches wide, mine are 9-70. The fronts are the same at 7-55 so get a 1 inch spacer for those. For the rears, I would jack the car up, put the new wheel in the opening where you want it and measure the distance to the hub from the lug nut flange. This measurement will be the amount of spacer needed. Obviuosly, take into consideration the oil lines,, trailing arm adjusting bolts and the outside fender lips. I am sure there is an equation you could use but I found that seeing it on the car helps me more.
Or you could just use the search function here. I am sure someone has put these exact wheels on an SC before.

Yellowbird RS · 07-05-2005, 08:27 AM

you need to get 17mm on rears and 23mm et in front
so 55-23=32 front
52-17=35 rear

jhelgesen · 07-05-2005, 08:55 AM

I ended up using 944 turbo spacers (aprox 3/4") on the 912-6 plus the longer studs. I used one set on the front, and two pairs on the back as my 2" spacers were too wide.

RarlyL8 · RarlyL8's Garage

I have a pair of brand new 1" adapters if you are interested.
Includes studs, spacer, and lug nuts. Bolts on to the existing hub.
You can e-mail me at the address below.