PatriYacht

Maybe if you use aluminum heads on a stock engine you can use a 180 degree therm. I prefer to run my 10 to 1 compression 540's colder to avoid detonation. Merc put 140 degree thermostats in all of their carbed engines along with jetting rich to be safe. Most supercharged engines run with no thermostat to get the cylinder heads as cool as possible to avoid detonation. It's really not good advice to make a blanket statement about running 180 degree thermostats. Also, don't rely on a couple of drilled holes to keep your exhaust cool and to keep your water pressure down when using a crossover. Always use a crossover with a bypass when using a thermostat of any temp. My bypass uses a 1" dia. i.d. hose to feed the exhaust. The holes are a good idea to eliminate the air pockets that form around the thermostat and prevent it from reading water temp and opening.

ckin62

I tried running with no T-stat and had an issue with condensation collecting in the pipes and headers. It was so bad that I had to pull plugs and pump the water out. At first I thought I had leaks. After pressure testing everything ruled leaks out. I put in a 140 t-stat and the condensation problem went away.
I'm running 540cid with procharger on carbs. and cast iron heads. I wanted to run no t-stat to keep head temp as low as possible.

tfarmer

I always use a by-pass hose with mine. He did not state using
one and ask how to drill his thermostat! most of the engines
ive done end up with a 180 stat. I dont run my engines around
at 150 deg. cold engines Dont run good in my boat.
NOT EVEN WITH A BLANKET.
Aluminum engines, high timing, low timing, Big boost, no boost
compression, jetting, fuel. everything is a big factor and one on one to your area and the water temp your running in.
Eddie marine showed me how to set up my first ones and it
has always worked for me using a by-pass hose so i don't have to rely on a couple of drilled holes to keep the exhaust cool.