Heat is your friend, heat is power. Heat makes nice idle quality. In a N/A engine you want heat. With saltwater raw water cooled you cannot have much heat without issues. A circ pump will help with heat distribution. Once yu go Fresh Water Cooled it is hard to go back.
Steve

I've never run a cross over so no 1st hand experience. But I would think you could get temps too cool/cold with either type.

I've half azzed looked into going with a cross over but have stayed with the circ. pump because it's dependable. On the other hand, allot of time there seems to be a bunch of screwing around to get the cross over/temps/water pressure the way it's supposed to be. Cross over is fine if you want to "clean up" the appearance of the front of the engine. Or want to get that last 5-7 hp (only what I've read). Personally I'm not into the bling enough to change over. And I have plenty of hp so I wouldn't even realize another 5-7.

Where can i get the cross over kit with bypass.

stainless marine or cpperformance.i like stainless marine myself.