Blaster Need some 'technical' data (pressure/temp numbers)

Maybe someone on here can get me some numbers.

The engineer in me has come up with a nifty cooling solution for my 701, involving some thermal bypass valves. The system I have come up with will keep each cylinder at a constant temperature, and I won't have to worry about restrictors/etc since the valves will take care of all that. So there are a few different temperature valves I can work with, but what's the 701 seem to operate best at? I was thinking 165 deg F, but I can go as low as 130 or as high as 180. Also, the system would only be able to handle 125 psi max pressure. I'm almost positive the pump cooling line doesn't put out anywhere near that, but does anybody know the actual pressure on that line?(assuming the line was clogged or blocked for my purposes)

I was thinking about regulating the pipe jacket temperature as well, to keep it at its 'best performing temp' but I don't know where to begin there. 130 maybe?


Edit- Oh and another benefit to all of this- faster warm up to proper operating temp. Should make the engine more reliable?
Has any one ever done something like this before? I know I've seen some old race Doo's with pressure regulated systems, but never for auto temperature regulation
 
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We used to stick a meat thermometer in the water overboard and the optimum temp seemed to be around 125F. Not that it was the end all be all temp but our race boats ran well and could last a full race with little heat soak fade, also no stuck cylinders. If your running a billet cylinder then I have no idea because those things run hot and don't transfer the heat as well as our cast cylinders did.
 

#ZERO

Beach Bum
Location
Florida - U.S.A.
If you're going to use a thermal bypass valve you may want to install a filter screen upstream because they will clog easy with debris since it's a restriction point. I would start with 130F for the engine temp and 145F for the pipe because anytime hotter would cause burns going overboard. Also I would install a temp probe before the valve to monitor the water jacket temp because the water pressure and engine rpm along with the reaction time of the valve will greatly affect your temperatures. You may just find out the valves won't respond fast enough to regulate the temperature inside the engine but it's a cool idea anyway.
 
Yeah I was worried about the speed of the valves opening. I talked to a rep at the place that makes them, he thinks they will work alright. He said the valves open and shut fairly fast, since they are used as safety bypass valves on the product they are actually made for. He was really confused when I told him I was going to be using them on a watercraft. I guess they use these on high pressure/temp power-washer pumps.
 
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