Water pressure
 

I have a boat with two 502/500 hp efi motors > What is the min. water pressure at 5000 rpm's to keep these motors cool? Also what is the max. water pressure you can run? I have rased the X diminsion and seem to have low water pressure now, even with low water bravo water pickup on housing. 38 fountain twin step. Thanks for the reply!

David,

You need to fry those engines so we can finally get around you :)

But then we wouldn't have that rabbit to chase...... As long as you've got 12 pounds of pressure you'll be fine, with an optimum of 15 up to 20. Anything over 20 pounds and you start risking gasket failures.

On my pleasure boat I'm running 15 pounds at 5400 on supercharged 500 efi's and haven't had any cooling problems. The raw water pump also feeds the intercoolers and there is still plenty of waterflow in this configuration.

In the GMC boat we're running app. 15 pounds.

Best to you, Roger, Tommy and the crew, look forward to seeing you all in Marathon.

Steve