I’m putting this in a new thread so that it can be searched easily instead of being buried in another thread. Richard has a thread “My Poor Dead Engine” and in that thread overheating was brought up. I made a 6-1/8” water pump pulley to overdrive the water pump a bit and test whether it helps low speed temperatures. I won’t take credit for the idea but I wanted to see if I could get my idle temperature down from 220-ish. I was talking with a friend who said he had a repop BBC 5-7/8” pulley from a ZL1/L78. He said it was 1-5/8” from the front to the center of the groove. I already knew my stock ‘70 Caddy pulley was 6.5” and 5/8” from front to center of the groove. Hey that’s 1” difference, as in a 1” spacer. I bought the pulley for $35 and a 1” spacer for $25 on eBay. Way less than $160+ for a billet pulley. Here are the pics. Oh, and I gave $17 for a 3-1/4” alternator pulley to underdrive a little compared to the 2-1/2” stocker. The belt ended up being in almost the identical position. I’ll update results after a drive.