455 water pressure??

[pancho]

Bought my old jet boat with no thermostat and would see 120 degree`s on long lazy rides motor likes a little heat installed a 180 degree thermostat with a 1/8" hole drilled on each side just in case worked flawless for 6 years not saying to do this just one of those worked for me deals

[ak49er]

I run a 460 with a tunnel ram, and a Pro billet MSD Distributor, supposedly for a Tunnel Ram 460. I ran across this guys site Performancejet.com, go to "tech Talk". He gives a great technical explanation of this ,"Full Block Volume, Regulated Temperature and Pressure conversion.

I followed his instructions and have had excellent results.

Basically I used a Watts Bypass Flow Control Regulator, Watts 5300A, adjustable from 0-100 PSI, with 1/2 NPT. It lifts at 12 PSI and dumps through a stern dump, I have a mechanical guage right on the Intake manifold.

The temperature is regulated by a Marine SS Thermostat, and I drilled two...maybe 3/16" holes in the flap. This allows steam pressure, and air pressure to bypass, so the thermostat won't lift under pressure, but "waits" for temperature.

The thermostat housing now dumps both ports , again through two other stern dumps. Now including the bilge dump, the boat has four dumps running across the stern.

[gatahiti]

I have often wondered if a more stable engine temperature could be had by running a recirculating pump like alot of I/O systems do.