I just posted a question on pulleys last week. My 68 with a short water pump was throwing off the belts at anything over 6000 rpm. The suggestions seemed to say go to March pulleys and the problem would go away. Well, I spent the $200 for a three groove crank pulley two groove water pump pulley and alternator pulley. The parts are all high quality billet aluminum but thats where the fun part ended. I have a B&M Powercharger on my Malibu and it has a spacer that has to fit inside the crank pulley. The reason the March pulleys stop belt throwing is the crank pulley is about 33 percent smaller than my stock part. The blower belt spacer would not fit inside this smaller crank pulley so I had to turn it down about a eighth inch to get it to fit. I also had to grind a few places on my water pump to get the pulley to turn freely without binding. I had to space my power steering pump out from the block about and eighth inch to get it to line up properly with the wider crank pulley. And lastly I couldn't use the alternator pulley at all; it won't work on my alternator. I have it all back together and it has stopped the belts from coming off, I can turn it over 7000 rpm now and no problems. These pulleys solved my problem but it was definatly not as easy of an installation as I had hoped for. Hope this helps you in some way. I think if I had it to do all over again I would just swap out all of my brackets and install a long water pump style system. Bob
