Engine cooling

[David Ashcroft]

How much water cooling do you use?
Or do not use?

Heat is good... but too much can be detrimental to performance.
I was talking to another boater and he says my engine is running too hot and is limiting my performance.I have watched his boat run which is fully cooled lower and upper ring, and it runs very good ..Talking 67 to bigblock monohulls.

 

[brad nichols]

It depends on cylinder head temp. somebody will tell you what it should be. He may be lean or he could use 2 separate lines to the head and ring
Brad

 

[David Ashcroft]

I always believed that the head needs good heat to perform,which in turn helps burn nitro .I always use the top chamber only but I also notice that the power sags after a lap or 2 and goes off pipe...The boater I spoke to says increase cooling and it will perform better...So I am going to test and see...

 

[David Ashcroft]

Don't be shy gents ...I believe my friend is correct ...of course there are variables

 

[dr gary turner]

I always believed that the head needs good heat to perform,which in turn helps burn nitro .I always use the top chamber only but I also notice that the power sags after a lap or 2 and goes off pipe...The boater I spoke to says increase cooling and it will perform better...So I am going to test and see...

You don’t need more cooling. You need MORE FUEL. It’s sagging because when the motor reaches operating temp after 2 laps there is not enough fuel

Richen the motor up run several laps then use your mixture control and slowly lean the motor down. THERE IS More power on the rich side of the needle

 

[David Ashcroft]

Yes I know your correct doc
..

 

[David Ashcroft]

Doc in theory when pipe is gradually shortened then we richen slightly to compensate for more rpm and heat...Which is why I am confused about incoming information..If I cool with water then nitro cannot be properly burnt..correct? I would like to agree that we should use more fuel to cool the top end and create power..
Marty Davis always said lower the compression and richen the needle for power.. Which I always do...
The variables I guess are weather conditions..too hot humid then we pull pipe and lean...cool weather we shorten and fatten needle...
Well our cooler months are approaching now so the power is ahead.

 

[David Ashcroft]

It depends on cylinder head temp. somebody will tell you what it should be. He may be lean or he could use 2 separate lines to the head and ring
Brad

Brad it's around 125 - 140f when she banks using a heat gun..

 

[dr gary turner]

I don’t mess with the pipe too much. Will adjust for prop load

I adjust needles with air density and flow changes.

With a good flow meter you can develop a “book” of data. Flow/air density