small block chevy to closed loop

I am converting a 1964 Owens 24’ flag ship complete re power
From 327 block and heads to a 350
Going from open loop to closed loop cooling. My plan is to use a mercruser salvaged tested good heat exchanger and using a 28gpm pump what thermostat should I use?
And any other suggestions?

 

The engine should be happy with either a 160 or 180 degree stat.

 

Use one of the non-toxic antifreezes, or when the system leaks (they all do, eventually) cleanup becomes much much more difficult and possibly legally entangling

 

thank you on the reply
i am finding impeller style pumps are rated to 180 deg f it is not possible to use a oem waterpump what are some ideas for a 220 deg max 12 vdc or belt drivin pump

 

You should be able to mount an automotive water pump to the 350. Just like a car it will be powered by a fan belt. Is there a reason you can't do this? The automotive pump with a metal impeller very capable of handling high water temps. This pump should circulate the antifreeze in the closed loop. You also need to pump cooling sea water through the heat exchanger in an open loop, intake from sea, through heat exchanger, back to the sea. Your 28 gph electric should work fine for this, it will not be subjected to high temps

 

the reason i cant use a standered w\p is it sits in there bacwards velvet drive transmissionis driven off the blancer end of the engine and a adtptor plate resticts placepent of that style of pump

 

water pump

Ok that makes sense. A water pump off a '60s vintage Ford 352 might work. It you will have to come up with a way to mount and power but it should do the trick.

 

i found a comany that makes a remote water pump and it will work great
from a racing aplication
my next broblem is a Y fitting best metal choice brass bronze ss copperor silcon bronze
i will be moving raw water in one fitting and coolant in the other

 

metal choice shouldn't matter so long as your metals are all identical. so find out what the pump housing and impeller are, and match that. easiest way to prevent galvanic reactions if you don't throw a zinc in(and even then, keep one in the open loop portion) is to keep everything identical, and make sure it's all isolated with non-conductive mounts(if you can) to keep a circuit from forming.