hello!
Doesn't feel good running without thermostat. I think temp vill be to low and also takes long time getting warm. Thinking of putting 160F tstats. Since I have crossover (no circ-pump) a bypass is needed. How to do?? Drill hole in tstat or a hose from just below tstathousing to top of tstathousing? Suggestions?

Engines are 468's, forged internals, cams for 5500rpm's. Picture of engines:
http://www.chriscraftstingers.com/ni...ttipaldi.html#

you need the thermostat, mine ran way to cold, I run a std merc 140 with a couple of small holes drilled in it, you need a crossover with a fitting on top(which you have) for the bypass and a thermostat housing with a fitting on top with a 90 deg fitting there and a short hose down to the crossover...eddie marine, CP has them just for that...Rob

I second on needing a t-stat. I tested with out one and the amount of condensation produced inside the exhaust was scary!

Most marine engines with superchargers dont run T-stats. I feel oil T-stats are something all marine engines should have, along with oil temp gauges. You can run thermostats and keep your water temp 140-150. Keep an eye on oil temps, that is what will cook your motor.

Lots of my friends including myself run blower motors with oil t-stats. Water temp gauge stays at 100 degrees all the time. Oil temp, you want to at least get 215-220*...to cold is no good, and too hot is no good.

Another thing to note is where you take your oil temp reading from. Lots of debates on this, but mine are taken after the cooler, before it goes into the block. Always stays on the cold side of the gauge, however, condensation is not an issue. I would like to add a gauge for the oil coming out of the block, so i can compare temps.

Water PSI gauges are a good thing to have also.

If I use a bypass, then there is no need to drill small holes in tstat? I've heard of people running without bypass, but with 3x 5/8" holes in tstat. But you suggest both bypass AND holes in tstat, right?

Regarding oil tstat... You say that high oiltemp is what cooks engines. But oil-tstat doesnt help that, it just makes sure you are not running the oil too cool, right?

The best solution is perhaps a 140 or 160 water tstat AND a 212f oil tstat...

You are correct, a oil stat won't help too high of oil temps. But, too cold of oil temp can cause spun bearings, condensation build up which can ruin camshaft, lifters, corrode valve springs, etc.

A 140 water stat, oil tstat, and a large enough oil cooler that will keep oil cool at sustained wot runs, and you'll be good. With water stats, keep an eye on your water psi

Run the bypass hose, you will need a different thermostat housing, the crossover you have will work fine. You drill small holes in the thermostat just to relieve the steam. I am going to try one of the high flow stewart thermostats with reliefs built in. I have heard of a few guys using them with good luck.

1/8" holes.

Ok.

(Those i've heard of running without bypass drills three 3/8" or 5/16" holes)

I run cross overs with 140 Tstats. N/A application. I have water pressure gauges and bypass valves. I am changing back to water pumps. You gain nothing unless you have a blower application. Looks cool but no gain in Hp.