hey guys im running a little too cool and am not running thermostats as i have crosovers. i wnt to bump my engine temps and am going to make 2 round plates to restrict water flow out of the thermostat hsg. what size hole should i start with. im running 130* wfo and wnat 150 to 160* wfo. any body ever do this on a boat? a friend of mine did this type of set up on a sbc in a chevelle and it worked well in his car. moroso sold a kit in alum, i want to make them out of ss. what is the od of a bbc thermostat? thx for any input. ratman

Try a search for thermostat you might see a marketable improvement!

The kits come in 5/8, 3/4 and 1" ID holes. The 5/8" still gave me to much WP, 1" not enough. 3/4" resulted in perfect pressure and somewhat acceptable temp. No idea on the OD

us1 fountain what was your temp with 5/8 and 3/4? what engines are you running? thx a bunch ratman

glh never did a search, my bad on sp, thx

us1 fountain, who made your kits? are the discs alum or ss? thx again, ratman

Mine where AL. You can buy them in a 3 pack from Summit and Jegs for only a couple bucks. Didn't run the 5/8 long enough to get a temp reading do to higher than desired WP. With the 3/4", WP was 18psi at WOT, temps right at 120* during the summer months. This was on my blower motor. Never could get higher water temp.

Summit: Water outlet restrictors,
Alum $7 pt #MOR-63440
SS $10. pt# CSI-900RP


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