Will a crank driven water pump, pump the same amount of water as a belt driven water pump? I'm looking to go with crank driven water pumps on the new motors, they are 496 strokers with about 600hp (I hope)

More than adequate. Innovation used them on the Volvo DPX 600's.

http://www.offshoreonly.com/forums/d...ter-pumps.html

I know this for a fact from Volvo Penta school they had to move the crank driven pump off the crank and go with a belt driven and larger pulley set up to slow it down because their newer LS based engines (the 380 hp & 430 hp) spin up to 6k rpms. They said the impeller cavitated at those high RPM's in which caused induced air into the cooling system in which caused overheating at full throttle. Anyways the point here is thru Volvo's testing a crank driven impeller pump is RPM limited.

i was running a neovane 755 cam driven pump and i was dumping a good 50% of the water into the exhaust and the rest went thru the motor and then a dump out the back while keeping a 180* engine temp cruising. from what i hear the magnaflow cam driven pumps flow even more.

I've been running the Magnaflow cam drivne pumps for 5 years, the last 2 with 177 blower and about 550hp. I don't run a themostate and the temp never gets above 100*

I really like crank driven pumps. With that said. My experience is that when you come off plane and losing the force fed aspects of cooling that the crank driven pumps smaller impeller moves less water at idle speeds.
Steve