In Reply to: Newbie wheel question posted by nobody on October 22, 1999 at 18:34:56:
OFFSET - the measurement built into the wheel that determines how far in or out of the wheel well it will sit. this matters a lot when you lower your car, because you would want them to sit further in (usually a higher number on fwd cars, so i'm not sure about rwd bimmers) to prevent rubbing and/or turning problems.
HUBCENTRIC - as opposed to lugcentric. well, hubcentric means the wheel is centered using the hub as a guide. all wheels have a center opening on which the wheels are balanced. correspondingly, there is a raise lip/ring on the axle hub onto which the wheel will fit. this ensures the wheel spins "round" properly and not "wobbly" when driving. lugcentric is just that, the wheel is centered using the lugnut, studs, and wheel openings. usually the wheel openings are rounded out. the rounded end of the lugnut fits into this depression. as you tigthen the lugnuts in the proper fashion, the wheel centers itself using the studs/nuts as the guide. (just an example, but i do know that the bmw "lugnuts" have the studs built into them; ie, the hub is completely flat.)
SPACERS - rings made of metal that fits in between the wheel and the hub on the axle. effectively, this pushes the wheel further out of the well, thus increasing the width (ie, track?) of the car. this is done for more driving stability. sometimes for looks. however, this lowers the amount of stud threaded into the lugnut so you might have to get longer studs.
: What's offset, hub centric, etc.?