I bought what I thought was a Z6 crank pulley, and when I put the alternator belt on the car it didn't fit, because it's a 4 rib design and the crank pulley only has 3 ribs for the alternator belt. I just cut a rib off the belt and it seems to be working fine, I'm just curious as to what crank pulley I have? It only has alternator and power steering belt grooves, no A/C.

 

Thanks for the input. I guess I'll keep using it as long as the custom belt holds