I have a 1940 Chevy coupe with a 350 SBC that has run hot for years. It has a Walker radiator that Walker repaired about 4 years ago so there is no stop leak in it. I have the biggest electric fan and shroud that Walker made and required a 50 amp relay. I have a 180 degree thermostat and on a cool day it runs right at 180 degrees on a VDO gauge with the sender mounted in the head.

On a hot day it isn't unusual for me to run 210+ on the freeway and if I hit a traffic back-up I have to pull off the road, lift the hood and let the electric fan cool it off back to 180. I really would like it to run cooler in stop and go situations. I also have a Stewart high flow water pump and my lower radiator hose does have a spring.

When Walker was in business they said brass cooled better while others said aluminum. I guess my question is has anyone went from a good brass radiator to an aluminum one and noticed a significance cooling advantage? I don't mind dropping the cash on a new aluminum radiator, but I'd hate to make that investment just to see no noticeable improvement.

I should note that my electric fan evolution has went from a Spal with no shroud, to a Cooling Components (Walker) with a shroud, to my current Walker fan and and I haven't really noticed a lot of improvement from the first to the last. Attached (I hope) is a picture of my current radiator and fan.

The only anomaly I can think of is my car has never had any inner fenders, which I think would allow more air circulation.

Thanks in advance for any ideas.