hpy540

I have started the sea trials and i am hoping to get out and do some tuning later this week if it ever stops snowing here . I have a few questions on the crossover setup for those who have run them. I had a 160 thermostat with 3 3/16 holes drilled in it in the intake and a pressure dump with a Gage. The temp was bouncing up to 230 when idling around and when i would cruse at speeds of say 25 mph it would drop again. to 180. I had a impeller problem, I fixed the impeller and no change in temp reading and stillnot building any pressure Even at wot. I now took it out and the Temp is at 180 or so when idling and when i plane off i am at 120 to 100 degrees. in no way dose the water pressure ever rise. The crank pulley i have is one with the center belt smaller dia so the pump is not spinning as fast as the rest of the accessories. should i change the bottom pulley so i am spinning the seawater pump faster? and put the thermostat back in so i can run more consistent temps. to me this seems a Little backwards for what the general consensus on the board is with these crossovers. Everyone here has pressure problems. We do do a fair amount of idling up here so getting the oil up to temp is not a problem. Also what if any hp gains would i n be seeing if i change from a Holley strip dominator intake to a say merlin or a dart? I am running a 850 carb and AFR heads 315 with .613 629 lift 236 244 lsa cam? I do am starting tolook for a decent used intake that would work.....

hillbilly24

On the T-stat issue I would cll Rev Marine in California, they have a great poppet valve kit that is designed for use with a crossover and will maintain water pressure and keep the temp around 160. The kit is like 100 bucks but it will solve all your colling problems.