anyone ever had an engine run to cool? like not even get warm enough to open the thermestat? I have always had the 4 core radiator in my f 150. When the engine was stock would get up to temp open the thermestat etc. With the engine now built for some reason it actualy ran on the cold side, wouldnt open up the thermestat, thought that was odd for a built engine to run on the cool side. Also it has a clutch fan. Was thinking that maybe the ported and polished heads with the edelebrock performer rpm air gap intake headers and the 1 3/4 headers could contribue to it running cooler? Just wondering what would cause this i already made a change to bring it up to the proper running temps.

Gave me the exscuse i needed to go to an electric fan hehe, now it goes right up to temp opens the stat fan kicks on cools it off. Seems the fan only needs to come on at an idle to keep it cool doesnt even come on going down the road. Was pleased with the electric fan i got for it to, didnt want it to look silly with this little fan on the radiator, got a 16 inch which fit inside the stock shroud and you cant even notice the electric fan in there

anyways any opinions on why it would run cooler?

 

you either have to cool a thermostat or its stuck open and not allowing the engine to warm up. When the thermostat is closed the radiator is bypassed. When it opens it alows flow through the radiator. When it sticks open it is always flowing through the radiator and never alows the engine to warm up.

 

I've owned two 351's.And they both ran cool, all the time. The radiator could be half empty(small leak over time), but the temps never ran up.In the winter, blocked off the radiator for heat. I replaced the T-Stats several time, put a warmer one in, still same result. The only time it ever heated up was when I would tow my 7000lb cargo trailer through the mountains, and even then, it didn't over heat.

 

its a 180 stat and i had the cap off to let it get open to see when the stat opened, this was at an idle of course, you could hold your hand on the radiator and it was only warm not hot where you would have to hold your hand back, switched to the electric fan and watched the stat open as you could see the antifreeze circulating

 

Must be something up with the stock fan. I've had mine replaced when the clutch froze up (you could deffinantley hear it). Repalced the entire cooling system, still ran cool.(my system was worn, and was springing leaks, 200,000 plus miles)