Thin spacers just have 5 holes for the lug studs. As they get thicker, they require longer studs in the hub. When they get to about 1" (25mm) they sprout 5 more holes with conical countersinks. These hole slip over stock wheel studs. The other 5 holes in the spacer (or adapter as some call them) have 5 stock length studs that stick outboard and are what the wheels then bolt to.
I think I'm partial to the bolt on spacers, with stock lugs, vs the slip on spacers with extended lugs. You can pick your wheel and tire combo, and then get the appropriate spacer to center it in the wheel well.
Click to view attachmentThese come in many thicknessssssesssssss. On my 914, I had a pair made up custom. One is 1" thick the other is 7/8" thick. This was to get the gap between the tire and the flare the same on both sides, as the flares are not precision parts, even the Porsche factory ones like I used. (I wouldn't do that again, 1/8" doesn't show, especially since you can't see both sides at once.) Anyway, between the 1" spacers and the 7 x 15 Fuchs, and the 195/65 R15 tires, I have a look that I like.
I also have 4-to-5 lug adapters in front, and they're 1" thick. I have original 914/6 parts for the front.... maybe next winter?
(needs ride height adjusted down, as well as rocker panels.... always something!)
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