Sold the 911 SC, bought a 2006 Cayman S

After six years of enjoying the 1983 911 SC it was time for something new and newer. So I sold the 911 and bought this 2006 Cayman S 3.4 in Arctic Silver with blue interior.
I've only had it for less than two weeks but am already loving it!
There are a few styling tweaks that will make it exactly to my taste. I've wrapped the fog light bezels in black to blend them in with the black grills for the radiators. I'm also working on something black for the side engine intakes.
But the most important mod are the Fuchs like wheels! To me Fuchs and Porsche are a match made in heaven and I'm still a bit of a classic fan. I think they suite the lines of the Cayman perfectly. I'm very happy with the aesthetics!

I do have some questions about the wheels. The ET of the front wheels is 50mm vs 57mm for the original Porsche wheels. According to Wikipedia a difference of 5mm is acceptable. So should I be worried about a difference of 7mm?

The ET of the rear wheels is 47mm vs 43mm for the originals. That's fine, but a spacer of 5mm was needed to clear the tire from the shock absorber. The spacer would lower the ET to 42mm, so near stock. But 5mm or less clearance from the shock absorber doesn't feel much to me. Should I go with a 10mm spacer to be safe? The ET would go to 37mm, 6mm short of the stock 43mm.
The rear wheels with the 5mm spacers are bolted on with the stock Porsche bolts. Is this not a problem, or should I go for 5mm longer bolts?

Thanks in advance for any advice!

Best, Peter

p.s. the wheels still fit fine within the wheel wells. I think 10mm spacers on the rear won't push them out to far either, there's still room as it is.
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At the front it's the same as stock; 8J. At the rear they're 10J, one inch wider than stock.
Correct me if I'm wrong but if the ET is the same, the 10J wheel/tire would get half an inch closer to the shock than the stock 9J? So about 12,7mm. The ET however on the new wheel is 4mm larger, so the tire has moved 12,7 minus 4 = 8,7mm towards the shock, causing it to rub. A 5mm spacer seems to have helped but I think I'll go for a 7mm or 10mm spacer just to be sure. That certainly means longer bolts, so that would be no longer a questionmark either. Tire sizes are the same as stock by the way (265mm). Which is fine for 10J but the max for 9J, even though Porsche recommends this size in their owner's manual.

 

Weather was too dark to take decent pictures. I wanted to wash the car before taking pictures, but as usual the weather forecast was wrong! I'll take pictures of the blue interior as soon as possible. Mind you, this is not some kind of smurf blue! It's a very decent, grey-ish blue. But something different from the usual black or grey.

 

By the way the car came with a Porsche booklet with all the standard features and options. One of the options are 5mm spacers both front and rear! But with longer bolts. So if the factory says so...

 

Hi Steven,
Thanks for the suggestion, much appreciated. The original Porsche bolts are used and they are conical, so I'll check the new wheels if they have the correct conical seats. I'm also going to double check the wheel measurements, especially the ET. I find it curious that the ET of the front wheels is lower, yet they seem to sit out further than stock. And if they indeed did move 7mm inwards, I think a 5mm spacer should bring it back close to the standard position, which I assume is always the best way to go.

 

I'm not a fan of spacers either, but I'm okay with no more than 5 to 10mm, especially when it helps to get the center of the wheel close to the original position. I assume that would mean close to factory suspension/wheel geometry.

 

Another question: when the length of a bolt is mentioned, does it relate to the total shaft, or just the threaded part?
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Well I've checked and double checked everything. the wheels are suitable for the OEM conical bolts, so that's fine.

The center line of the front wheels has moved out 7mm compared to the OEM wheels. No spacers so no longer bolts needed. As Porsche is fine with 5mm spacers on stock wheels I don't think 7mm is a problem. They fit well all around (the ride height is OEM by the way).

For the rear I've ordered 10mm spacers and 37mm bolts (OEM bolts are 28mm). I've checked the room between the tire and the shock with the 5mm spacers currently on and I'll be more comfortable with the 10mm spacers instead. The center line of the wheels moves out 6mm compared to stock so no problem there.

Thanks especially to Steven for the advice!

Best, Peter