[Matty8]

I have put a 400 sbc in a tractor to use for pulling. I am using the tractor rad which is small and it overheats. I am going to put one or maybe two electric fans on it and see what happens. Should I take the thermostat out or will that make it worse? Are there any other tricks to make it run cooler. oh and I do have 350 heads on it and I did drill steam holes and I'm using a proper 400 head gasket

[Ruthlessmr]

fill the block if you can
stock heads or aftermarket?

[vinniekq2]

build a shroud and use a big rad,tractors are slow so need help with air flow

[Matty8]

The heads are stock

The rad is just as tall as a car rad, but not as wide. But it is 2 or 3 times as thick. I can only fit the stock rad in the frame and sheet metal

[Ruthlessmr]

underdrive pulley for the crank
how long does it need to run?

[PatM]

Radiator performance is like a heat exchanger. Indeed, it is a heat exchanger. Cooling fin area and air volume/velocity are the primary variables. A good fan, an appropriate shroud, and it should work. Particularly for short pulls. The are other variables. Larger is better than thicker, but with enough airflow, almost anything can be made to work for short runs. Confession:this isn't based on experience, but simple theory. Don't remove the t'stat. If it's opening, that shoud be good enough. Get lots of air flowing, and that'll require a good shroud as well as a good fan.

Opinion.

PatM

[CNC BLOCKS NE]

Small Block 400 Cooling Tricks - Tech Article - Chevy High Performance Magazine

[lg1969]

Replace the heads with alum heads and change the thermostat to 160*

[Matty8]

The rad already has a shroud built on it. none of the fins are bent. how close should the fan be to the rad?

could I try drilling holes in the old thermostat

[Matty8]

how fast should an electric fan spin rpm wise