Quote:
Originally Posted by Otto
Ideally, the wheel cover would be a smooth, slightly convex disk extending to the outer bulges on the tire sidewall, to make the wheel/tire have as smooth a face as possible.
See also Sig. Hoerner's cites and pics in his Fluid Dynamic Drag, which covers this nicely in various aircraft wind tunnel studies.
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I had seen MetroMPG mention this before as well. I had these wheels covers :
that I bought for cheap. Unfortunately, I misplaced them, and they no longer make this style.
I took them off because they were convex and I
thought that they did more harm than good, since they would increase the frontal area slightly.
Please expand on this subject for me. I'm curious how that a convex cover can be better than a flat surface. ( I'm
not doubting it - just confused. )
I have been to a few junk yards to look for flat covers, but none are 13 ".
The hub caps that are cheap at places like AutoZone are all the chrome 'pimped' style covers. Replacement hub caps online are a 'friggin' joke. $ 80 - $100 ... for hubcaps ??