So I get this new engine put together, and the car runs good but water temps are much higher than normal. On the old engine it would be around 180-195, but no higher even during track use. Now with this engine, if I drive normally, keeping the RPM's under 3k the car will run right about 185-195. But if I get on it, the temps will shoot way over 210, and keep rising. The highest I've seen is about 230 and at that point and time I turned the car off and flipped the electric fan on manually to cool it back down.

On the highway cruising about 70mph the water temp is about 215 or so. If I run the manual fan switch at this speed it will bring the temps down to roughly 205, which is better, but I don't want to rely on it.

Engine is a rebuilt 5.0, with aluminum heads, cam and intake. Running stock waterpump w/underdrive pulleys, 160 t-stat(also have a 180), stock radiator and stock electric fan. I just can't see how adding aluminum h/c/i can make that much more heat! Also running full synthetic oil, if that contributes to heat or not I'm unsure.

I just ordered a Fluidyne radiator, which is a 3-core aluminum unit, hoping this will solve the issue. If not...man, I really don't know what to do, probably change the water pump to a high flow piece.


*sigh*

 

Forgot to add, the car runs great at 180 degrees or so, but once it gets closer to 210 it begins to feel sluggish. Maybe it's just my imagination though.

 

hmmm sounds like a fudged up thermostat to me... id give that a check, make sure your hoses arent pinching as well... that could be fouling thigs up. good luck bud

 

http://www.tricitiesmustang.com/forums could be a couple different things. let the stang guys put their heads together.

 

not that it matters much to the problem, but running synthetic before break-in???
was the cooling system bled properly? did you pressure test the radiator?
sometimes that underdrive pulleys cause heating problems.
don't shut the car off when it's getting way too hot like that. you'll warp the heads. the water that is flowing will help to keep it cool.

 

it could have a big air pocket in the cooling system