Hey guys, Just picked up this boat from a local guy. its a 97 model. Mint shape. Mag 502 EFI, Inter cooled Procharger. Aftermarket exhaust through the hull. Bravo 1 out drive with a racing lower unit. 28P prop that's been sent off twice to get tuned to the boat. Dual full hyd steering. My lake is about 3000 feet above sea level. One thing I noticed is that the water temp never broke 100 degrees F. While sitting with the engine off it did raise to 120 once but cooled back down as soon as I took off. Last owner said his fastest GPS speed was 89 last summer when it was real hot out, mid summer. Seems like this boat should be faster....? Right now its running mid to high 70s .. Im thinking theres no thermostat in this thing. My exp with engines tells me a motor will run better and make more power when its closer to 180 degrees. Would the same apply here?

My other thought was to install a ball valve in the lower 1.5" sea hose coming in to the boat going to the bottom of the sea pump, so I can slow the water flow down a bit and get this motor up to temp. Is that an ok option as well or will that hurt something else? In our mud racing trucks a lot of guys run no T stats and just restrict the water flow to build heat.. Any ideas would help, Thank you!

That's about where the blower motors run, Pro Charger doesn't recommend a thermostat, the extra heat at 180 may cause detonation and blow the head gaskets.

That's interesting.. I can see a guy not wanting it to run to warm but the intercooler should keep the air coming in nice and cold so it shouldn't detonate. Everything I know about engines tells me it shouldn't run that cold.

Last week we ran it. Did about 75 mile an hour top. Seemed slightly sluggish in the upper rpm and didn't seem to want to pull to 5k like normal. Let it sit for a bit the re fired. The temp had climbed to 120 ish while it sat, took off she ran to about 5grand, 79 mph for a sec, temp dropped back to under 100 and she lost the top end again.. Acted like for that few seconds the engine was warmer that it ran better. Just like it does when its 100+ degrees outside and the water has warmed up.. I live in SD where the water freezes during the winter and is still cold this time of the year. I can see not running a T stat when you live in a year round warm climate or something...

What I hurt anything by restricting the inlet flow of the sea water by installing a ball valve in the lower 1.5" hose just to see if I can get it to warm up some and see how it runs?

What model ProCharger is it ? how much boost are you running ? what do you know about the tune ? is it running in warm up enrichment mode at 100 degrees ? is the transon black with soot ? the cold motor will run fine if it's tuned right.

Its the M3 inter cooled kit. Only at 5 psi. No black soot anywhere. Not sure on the tune or if its stuck in cold mode....

Are you running cast iron heads ?

Aside from the bolt ons, the motor is stock. I think there cast iron but I never looked that close. I'm a Ford guy, I don't know these Chevys by heart lol.

What he asked Post#4 and you don't know. The guy is local so ask.

It sounds as if this is your first boat.

If so, since you are 10+ mph off it could very well be your trim and/or tab settings.

If so #2, please be very careful. Some boats can go from nice and stable to uncontrollable within 1 mph or 1 click of the trim and/or tabs / or a wave or etc. Especially at speeds you running and what the boat has done.

Edge up on speed and , again, don't assume each additional mph will handle the same.

I do believe they are cast iron, if you warm it up you may pop head gaskets on a long wide open run. I think it would be wise to find out what you can about the tune. Pro Chargers make good top end power, and when they are dialed in right, they just want to keep on going.

The guy I bought the boat from has had it several years and hasn't changed a thing. He didn't know anything about the tune either. He's never had any trouble with this boat so he never looked in to anything.. Its been very well maintained. Yes this is my first boat so that's why I'm asking questions before I make any changes. Most engines run better warm, even with blowers/chargers and turbos so I assume this is no different. If I'm wrong, tell me. Maybe this boat engine should run at 100 degrees.... The guy I bought it from took me out in it twice before I bought it, he mentioned it runs stronger as the lake warms up around here...