Is there enough of a gain with a 6 blade over a 4 blade fan? I thought I saw on here where to get the smaller pully and spacer. I'm doing everything I can to help cool the car down before I have to pull the heads and drill in the steam vents.  Thanx

       

Gary, 55 Vicky, St. Germain, Wisconsin

 

Don't expect the steam vents to fix it.  There's something else wrong with the cooling system that needs fixed.  They didn't overheat when they were new.  No steam vents and no 6 blade fans.

John - "The Hoosier Hurricane"

I’m in total agreement with John.  The steam holes are not for additional cooling but were provided to solve a problem with air being trapped in the block when the coolant levels got low.  I go out of my way using blocks and heads that do not have steam holes as they are inheritently stronger and less prone to cracking.

Boiling the water out?  If not then double check the gauge for reading correctly.

Lorena, Texas (South of Waco)

Thanx for the comments, it only gets hot when I'm in heavy traffic or on the interstate, & if I turn the heater on it'll get around 195, without the heater 200+. The radiator was checked, it's clean, napa #6 stat. The block was cleaned when the engine was built. It has the original water pump?, and I've checked it with a temp gun at the sensor and it's close.

       

Gary, 55 Vicky, St. Germain, Wisconsin

 

Any mods that might make the stock cooling system inadequate?

If it's getting hot while on the interstate, that's when the air flow across the core should be pretty high, then I don't think a different fan will help at all.

Have there been any repairs to the radiator in order to stop a leak?

Is the radiator unobstructed?



The #6 stat should be 170 deg, right?



Lawrenceville, GA

Is your heat riser opening all the way? That'll retain a lot of heat at highway speed, if not...

BOO- YA!!!

Tested the radiator flow at the radiator shop, water came out as fast as it went in, guy says it in excellent shape. Heat riser is gone. Rv cam, large valves in 272 heads, pertronix, 465 holley, FOM, dual exhaust. Possibly the pump is just old and not moving enough water. 

       

Gary, 55 Vicky, St. Germain, Wisconsin

 

What I mean about the radiator is one way they "fix" leaks in the core is to completely block off a tube. When that is done, the ability of the radiator to cool the engine is diminished. Even with some of the tubes blocked, it can still flow enough water through but it will not be able to cool as efficiently.



Did it cool well before the build?


Lawrenceville, GA

If it’s not losing water, then it may not be overheating.  Up to 210°F isn’t a show stopper and the engines are actually more efficient at the warmer temperatures as long as coolant loss is not a problem.  Engine wear is also reduced at the warmer temperatures.

What distributor?  Is the curve working properly?  The timing being too far retarded with the engine running at speed will also cause the engine to run on the warm side.  A properly working vacuum advance on any of the distributors will also help to keep engine temperatures down.

Installing a restrictor in the coolant bypass hose could possibly help.

Lorena, Texas (South of Waco)

Are your brakes properly adjusted?

BOO- YA!!!