I was just wondering what everyone thought was the optimum thermostat to run with aluminum heads or if it matters.

I have a 90 roller 302 with Edelbrock aluminum heads, intake, and carb. It currently has a 180 T stat. I know that most people recommend running a 190, but I was wondering if having aluminum heads makes a difference or not. I was thinking that if my car had a 190 in it it might burn the fuel more efficiently. Thoughts?

 

i wouldn't think alum heads would make a difference to thermostat selection. i believe stock is 190, mine is running a bit cold as well.
the only thing I'd do is to use those things that block the exhaust crossover in the intake ... (at intake gasket) and that's that

 

I would run the hottest thermostat that I could get by with that doesn't cause overheating. A 195 would be great, again as long as it doesn't overheat.

Higher heat is a good thing for engine longevity. It allows the acids to boil out of the oil. It will cost a fractional amount in the power department.

The aluminum heads, at least in theory, will conduct more combustion heat into the coolant, so radiator capacity will have to be adequate.

 

I agree with MBDiagMan. Engines are designed to run between 190 and 212. It seems counterintuitive, but your engine needs to be hot to run effiecently. The car manufacturers have done years of testing searching for the right 'sweetspot' and have come up with a 192 degree thermostat. On modern mustangs, the cooling fan switches on well above 212 (if memory serves, it is at 220, could be wrong) and if temp was causing problems for the engine, you can rest assured, Ford would do something about it to reduce warranty claims.

A hot engine does have a more complete combustion process. The key is to keep it in the sweetspot range. To many people try to solve overheating problems with the thermostat and ignore the too small radiator or internal cooling problems.

 

True, MustangBradley, or air flow issues. I run a 190* thermostat in my car. I always had issues in traffic until I reworked the condenser mounts so it was parallel to the radiator and installed a big block fan and shroud in my small block car. I was simply not getting enough air flow through the coils. Overheating issues have been gone ever since.

To reinforce what MustangBradley said, NASCAR engines run like 220*, but to keep them from blowing a bunch of water all the time, they run highly pressurized coolant systems. Liquid boils at a higher temperature as pressures rise (learned that in thermodynamics class in college). You and I really cannot run more than 16-18psi even with aftermarket parts, so 190-200 is about right.

 

Hottest stat without detonation.

 

Ford intended these engines to run on a 190° thermostat. I like to use the Ford one, because it has a little bleed valve that makes it really easy to put the coolant in.

 

I remember seeing that before about the bleed valve on the Motorcraft T stat. I like that.

I'm going to pick up a 190 T stat and swap it out.

Thanks for all of the input guys.

I have a Fluidyne aluminum radiator and the car runs good and doesn't get hot even with the AC on.

I'll post back after I get it changed out and drive the car some.

Would this be the one to get?

http://www.oreillyauto.com/site/c/de...3442&ppt=C0331