Water outlet restrictor kits

[motoxscott]

Rather than using a thermostat in my new 408 stroker motor I'm going to just run a restrictor washer to start with in the thermostat housing. What size would you recommend using? They come in a 5/8", 3/4" or 1" hole.

- Scott

http://static.summitracing.com/global/images/prod/large/mil-16420_w.jpg

[JEFFRPM]

Start with the 3/4 then see if it will stay at 210 in a sand wash pulling a grade for 10 minutes if not go larger. if it still can't cool off DO NOT REMOVE RESTRICTOR get larger fans,radiator.

[partybarge_pilot]

Restrictors are crap, run a umbrella style thermostat with bleed holes in it. Do not run a bypass hose.

[movindirt]

What about one of these thermostats?

http://www.motoradusa.com/products/failsafethermo/index.html

[gcddarren]

start with the mid size ring. if it gets to hot go bigger. 210 is a really good temp to stay around when going through a wash. 230 240 you loose a lot of power!

[John F2000]

The only big negative to a thermostat in a race motor is that they normally fail closed, and thus overheat. I cant remember where I found it, but someone makes a thermostat that fails in the open position, so it will never overheat as a result of the thermostat.

[John F2000]

What about one of these thermostats?

http://www.motoradusa.com/products/failsafethermo/index.html

Didnt see this before my post. but I think this unit opens in a high temp situation. The unit I found actually fails to the open position, not sure if it is the same.

[scottm]

Thermostats are better than restrictors, as temp fluctuation and running too cool are bad too. I bought a fancy $14 Moroso tstat that opens with a rotary motion, so it supposedly wont jam closed from water pressure at high rpm. It only worked for about 4 hours of run time then it effen stuck closed. My engine hit 260 but by luck didnt crack or lose the head gasket. Replaced it with a $5 stant that I drilled a .050" hole in. Now I also have a warning light with a 230° temp switch in the block.

[Ol' Curmudgeon]

Now I also have a warning light with a 230° temp switch in the block.

Good idea!