I am building my 1950 3600 wth a 383 SBC that was originally a 1991 CK2500 350 engine. I obtained a new short water pump from Summit as part of the build.
I received a water pump pulley yesterday and found that it uses the smaller bolt circle mouting holes in the water pump (the pump has two sets of pulley mounting holes, one smaller than the other). The pulley also appears to sit at least an eighth of an inch further from the engine than the crankshaft pulley and has that much clearance to the water pump. I have contacted the supplier to determine their return policy.
The fan/clutch from the original 1991 (long water pump I believe) uses the larger water pump bolt circle so the pulley and clutch/fan can not be bolted in place as is.
I am wondering if anyone running a SBC is using the clutch/fan arrangement or if it will be too long to fit a radiator (not sourced yet). If so how did you resolve the clutch/fan fit with the short water pump pullley (different bolt circles). I anticipate that an electric fan and shroud arrangement would be shorter and avoid the bolt circle problem if I need to go that direction.
I am also wondering if there is a preferred source for the short water pump pulley. Alan Grove (where I obtained the crank pulley and alterntor mounting bracket) is out of stock and buying from E-Bay sellers appears to be a gamble.
