Bored&Stroked
Well-known member
There are tons of myths about flatheads and moving the water TOO fast - personally, I think most are just that. I used to listen to this stuff - and on my stock 39-48 pumps, cut off every other impeller and drilled 1/4" holes in the rest (that was what I was told was the hot ticket). Today - I believe the reason that that "fix" worked is that we had a terrible impeller design - lots of cavitation and no flow.
I use 'Stewart' mechanical pumps in some of my late model race engines - they are recognized as some of the best. So for those of you who think you need to slow it down - here is what they say:
Higher coolant flow will ALWAYS result in higher heat transfer. Coolant cannot absorb heat after it reaches it's pressure corrected vapor point. Furthermore, coolant absorbs heat at a progressively slower rate as it approaches this point
I use 'Stewart' mechanical pumps in some of my late model race engines - they are recognized as some of the best. So for those of you who think you need to slow it down - here is what they say:
Higher coolant flow will ALWAYS result in higher heat transfer. Coolant cannot absorb heat after it reaches it's pressure corrected vapor point. Furthermore, coolant absorbs heat at a progressively slower rate as it approaches this point