[Tripower455]

Originally Posted by bignate

Even tho the exits aren't blocked, if there is nothing creating a low pressure area the air will not be drawn through the radiator. Think Trans-Am fender extractors or air dam under front bumper. As good as ram air is in the grill area if there is not a low pressure area it will just be like there isn't an opening for it to go through.

It's completely stock in that regard, and was fine before I put in the electric fan.

[lust4speed]

I was adding Freon to the '67 cruiser yesterday with the idle around 1,600 RPM. There was a larger flow of air coming forward under the front bumper than was being pushed out the rear. This high pressure area would sure screw up the proper airflow through the radiator at speed.

I always wanted to add an air damn under the goat. I picked up a plastic air dam off an S10 and it's a little wide. I figure that it could run just in front of the tires and hook to the bottom of the radiator support. Keeping it flat black would make it pretty hard to see unless someone was looking under the car.

Another idea I wanted to try instead of the air dam was a thin flat plate installed to the bottom of radiator support and running rearward past the sway bar and terminating at the front of the cross member. It could even have a 45° lip about 2" down at the back.

Either one (or both?) of these additions should create a low pressure zone in the engine compartment and really suck the air through the radiator at cruising speed.

[1967Tempest]

Originally Posted by lust4speed

Another idea I wanted to try instead of the air dam was a thin flat plate installed to the bottom of radiator support and running rearward past the sway bar and terminating at the front of the cross member. It could even have a 45° lip about 2" down at the back.

Either one (or both?) of these additions should create a low pressure zone in the engine compartment and really suck the air through the radiator at cruising speed.

That sounds like a good idea. You would never see it!!! Plus I think the 68 Firebirds have something like that. The sway bar never moves. I might try that the next time I have to remove the radiator. Mine is sweet, and cools AWESOME!!, but I will try anything if it helps....

Dave

[hookemdevils22]

I'm going to add some info to this thread. For the non-OEM-AC guys (15 1/2" core), a Ford Contour dual fan works perfectly. Grandville, it looks like that's what you have (had?) judging by your pics in one post. The Taurus (and Mark VIII) fan is too large. I understand that the Contour fan flows a little less than the Taurus/Mk VIII, but still pulls some serious cfm. Here's some info from the DC Controls website:

Taurus Fan (15.5"H x 20.5"W x 4"D)
Note that the fan itself is 17", which is larger than the 15.5" core height.


Contour Fan (15.875" x 24.19" W x 3.4" D)
Note no fan "overhang".


A small amount of trimming along the top (or bottom) is required to fit the Contour fan, but it is minimal (~1/4"). I'm using a Flex-a-Lite variable-speed controller (like the DC Controls) with brackets I had left-over from an aftermarket trans cooler. The radiator is a two-1 1/4" row aluminium Mark7 unit. I may switch to a standard temp controller with a heavy-duty relay because it cycles the fan after I shut off the ignition (instead of the one 30-second run it's supposed to do), and seems to be running the fan only at part-speed (because I'm somehow getting hot now). Here's some pics of my setup:

[1967Tempest]

That does look like a nice set-up for a downflow radiator. Let us know the results. I am ALWAYS looking for ready spares!!

Dave

[vidguy]

How did you you screw the brackets into the radiator hookemdevils22?

I was watching a 2 Guys Garage episode, and he drilled into the radiator and pressed in some kind of "nutsert". Is that what you did? How can you drill into those and not have to weld to assure no leaking?