Just courious, I have been studying the differences between the Gen IV(1965-1990), Gen V(1991-1995), and Gen VI(1996-present) Big blocks. One of the "improvements" from Gen IV to Gen V is the water jackets. When the blocks were cast, the jacket holes on the deck where the heads meets the block were enlarged to allow better coolant flow. Does anybody know if there is much difference in operating temps from the Gen IV to Gen V's?

Bill

Steve I have a 69 big block it runs between 190 and 210 most of the time.The owners manual says 210 is normal.On hot days 90 degrees or hotter my car would go to 220 or 230.I put a high flow water pump and 190 high flow themostat.This fixed my problem.