Does This Debunk the "Coolant Can Flow Through the Radiator Too Fast" Idea???

harrisonm said
That brings up an interesting point I had not thought about before. Why not just put a very slightly larger pulley on the water pump. For instance, going from a 6" pulley to a 6 1/8" pulley gives you a circumference increase of 1.19" (a 4.2% increase). Wouldn't that make the pump spin a bit faster and, therefore, move the water a bit faster? I would think that the impeller design will eventually be maxed out and not allow an increase, but 4% over stock should not reach that maximum. What do you think, @Newbomb Turk?

I believe it’s all RPM related. Just kinda like a Roots blower, you have a speed in which the blower doesn’t make any more pressure and just adds heat.

In the world of AA/GS legal stuff, the best we could do was about 54% over. Any more that that IAT went through the roof.

When they went to the 5 speed and started shifting at 9200 rather than the 8500 we were at, we had to slow the blower speed down some so that it still only turned the blower at 54% over.

The car went faster due to more gears and more rpm and the blower made the same boost. Or close to it. That was quite a bit of time ago.

I believe the water pump behaves the same. If you over speed it you can run into cavitation and probably some other bad things.

When I get a minute I may do some math to determine how fast you’d have to over drive a pump at 7k to keep it at the same speed that it sees at 5500.

One other thing. Like all things some of what else we can do is limited by what we have to work with.

There is a minimum diameter you can make the water pump pulley and a maximum you can make the crank pulley and get them to fit together.

If the minimum WP pulley diameter is say 5.75 inches and the crank pulley is 7 inches that’s only 22% over. But whatever those sizes are, that’s all the faster you can turn the pump unless you increase the rpm.

Somewhere in there is where the most effective cooling happens.

I don’t think you could even fit pulleys to go 30% over unless you spin the engine 10k.