My 422 smallblock build

View attachment 1715681271 View attachment 1715681273
I used this washer which I ordered from Fastenal after measuring the rear flat tips of the impeller. I then cut it in half and flux core welded one half on and then the other onto the flats on the backside of the impeller. I then took a grinding point and cleaned all the welds up. My minimum clearance inside is around .040 or so where the inside of the pump has an irregular surface pattern. Water is pulled in through the center of the washer around the driveshaft and then thrown outward by the vanes (just like in an actual large scale pump, but just cruder). TIG welding it on after pulling the impeller out of the pump would really be the preferred way of doing it. But I’ve tested it on the engine with a belt looped over the Chuck of a drill and spare pulley bolted onto it. It really moves some coolant without a thermostat in the system and the bypass blocked. I’ll add a thermostat if I find out I need one but I’m more concerned with seeing if I can just get it to run cool with 10:1 on iron heads and a 22 inch two core copper and brass radiator, a clutch fan, and a good shroud.
Thank you! Just in case, I already have a gutted thermostat set up as restrictor, if need be. Guitar Jones has an interesting read on cooling systems as it applies to dirt track racing and a small block Mopar. With the extremes encountered there, he has to restrict coolant through the forward cooling passages in the deck, block the bypass, and run without any type of restriction.