Reply to "Need new fans and radiator"

Larry,

Here's my 2 cents;

I have heard of Fluidyne aluminum radiators failing, they are then almost always throw away items. A brass radiator can be repaired by any competent shop. The aluminum usually has weight advantage, but key for cooling is the tube size, typically the tubes in an aluminum radiator are 1" or bigger, whereas 1/2" in copper. It is worth spending some time to compare the offerings and tube sizes the various manufacturer are incorporating, I have only heard good things when it comes to Ron Davis radiators.

Puller (sucker) fans are roughly 20% more efficient than equivalent pushers, I'd go that route again, but next time I'd get the highest cfm SPAL fans that fit and fabricate my own shroud for them.

I too made a stand off for my Flex-a-Lite fan shroud as mounting it directly to the radiator positions the fans too close (requires minimum 3/4" air gap) leading to a significant efficiency drop.

I think Johnny Woods was one of the first to discover that the Flex-a-Lite (and other) shrouds impede air flow at sustained high speed (allegedly 150mph in his case). He incorporated flaps that open via the higher air pressure at speed.

Julian