I am building a 383. Wanting to use Aluminum Pulleys. I talked to March Performance today and they say to use part no. 5072 water pump pulley( it is a 2 groove) part no. 510 for power steering( 1 groove) and part no. 5051 for the crank. It is a 3 groove but only a 5 1/2 inch pulley. Stock is somehwere around 7 inch. Has anyone used a 5 1/2 inch pulley on the crank? This will also have air cond. I am using a G.M., Corvette,  aluminum water pump/ 3/4 inch shaft. I will be running about 9.5 to 1 compression and approx. 400 h.p. Do you think I will have problems with engine overheating? Driven only on the street. I appreciate any advise from  anyone who has experienced this. Thanks! 

I tried a set and always had trouble with alternator performance.

Looks like I've come to the right placeMy new ZZ4/395 HP will be shipped at the end of the month, I'm trying to get the balance of parts that I will need, I'm currently looking at the same pulley set from March as you have. But, part 5051 is a tad larger 5 3/4 in 3 groove crank pulley? My problem now is the brackets for the alternator and AC. They wont fit with the headers installed, so my measurements say? What are you using for brackets? I will be keeping in touch to find out about the performance of everything? My change over will not start until the first week of April..Terry

I was out in the garage the other day and came across my reciept for my pulleys. I bought the 5030 set at Summit. My setup has the crank pulley, the alternator pulley the water pump pulley. It is underdrive and I have no problems with over heating or alternator. But, I do not have AC or a big electrical load on my setup either.

March 5030 Pulley Set

This is the setup I have and the same price I paid on 4/09/02.

Eddie 70, What are you using for your alternator Brackets? Would this work for my 73? I  am using factory G.M. aluminum short water pump for Corvettes. Is your crank pulley a 5 3/4 inch pulley? I do have a new polished 100 amp single wire alternator. Should be o.k.? Thanks!

Silver 73, I have found an alternator bracket that is universal, it bolts up on the drivers side to aluminum heads on the ZZ4 motor. The part is a zoops part numer 8120, I can't find anyone who makes a bracket for the GM AC that came with the 1976 vette, so I will adjust the bracket that came from the factory. I'm staying with V belt drive, if you going serpentine then you need other stuff..

Thanks,I assume it is an aluminum bracket. I am using cast iron 186 Double Hump heads with accesory bolt holes so it should work, I assume.  Is there a web sight for zoops? I think I have heard of it. Thanks for the help

Yes, zoops.com or you can get some items from Summit racing..

The alternator bracket is a Zoops one. I don't recall the part number right now but I may be able to look it up and post it here in the morning. Will let you know if I can find the reciept for the bracket.