302Sport

Anybody have a tried and tested system for an engine making that much power????????

WildThing47

Mercury....

The heat exchangers still require raw water to cool the existing fluid, you can even get kits for the 1075 to adapt them, not many people know you can do it.

I'm not sure how well it works in real world...but I do know mercury will supply a kit for most of their EFI engines, you can build one for the engine...maybe others have done it in real world scenarios can comment.

Most of the time I'm going to predict noone does it, due to the simple tear down times for high hp engines...you're trashing the heads after 2-3 seasons in salt anyway...and anything is usually being flushed and redone on 30-50hr tear down intervals of big power. Not to say you need to, but that's the main reason I'm betting not many do it.

302Sport

I agree but it's hard to argue with perfect oil and water temps every time out and no salt related issues.

Young Performance

Years ago, Racecrafters had a pretty large engine (1500 or so) with closed cooling. THey put the heat exchanger under the engine. The biggest drawback was the size of the heat exchanger. The one they used was HUGE. It looked like a 55 gallon drum under the engine.

I would say that packaging is the biggest reason that most don't do it. It hard to find enough room to install a heat exchanger that large and keep it on the engine so that it is self contained and not seperate pieces.
Eddie

Precision

In a Fountain you could just about put two HUGE heat exchangers where the saddle tanks would be.

302Sport

there are no saddle tanks in my boat and the motors are staggered so the tanks could go there

Mbam

We've done it since the 80's. The heat exchangers were never sized scientifically, just used the biggest we could fit in the boat. Today I would do the math and try and keep it compact.

No such thing as a kit, everything was custom fabricated.

The red engines were in my old Cig, 1000 HP circa 1990. The other setup was a 47' Apache we did in 1995, made over 1200HP on 89 octane. Note the thermostat housing and the water outlets on the cylinder heads. We found moving a lot of water was key to preventing detonation. There are 2 thermostats in that housing - the water passages in the intake are nowhere near big enough. These were low rpm engines (5600 rpm) so the circulation pump was overdriven.

302 - I think you are on the right track. With the constant temps you can put the clearances where they belong. Oil consumption is essentialy 0 - you change it before you need to add any.

302Sport

holy plumbing haha, what would it be cost wise to replicate a system like that, and who could i send the boat to for somebody to do the job? did you fresh water cool the intercoolers, and if so wouldnt the hot water going through the intercooler mitigate the effect it is supposed to have?

Mbam

Yes, in fact we did cool the intercoolers. Back when we did this the cores were aluminum. Today with the cuprinickel cores most likely I would not.

They were on another circut and I know we did lose some effectiveness. On the Cig there were 3" x 24" exchangers right after the sea strainers, the coolant was circulated by electric pumps. On the Apache there was a 4th heat exchanger for the intercoolers and a stainless circ pump driven off the back of the blower on the center engine.

I have no idea what the cost would be today, the heat exchangers themselves are not too bad. It is the labor & fabrication that is $$.

Not sure where to send you, we don't do this kind of work anymore. Hard to convince a customer it is worth the money.

delsol

Marc did you have outlets on the back of the head also as 7&8 are usually the warmer ones no?

ditto on the plumbing -- looks like a pipe fitter from a food processing plant did that with all the stainless...