Fan Shroud Gap

[Cory]

Hey guys I have a 73 Challenger with 440. My radiator is a 26” four core champion aluminum radiator. I’m using clutch fan with 7 blades. I’m using a mildon high volume water pump and Mildon 180 high flow thermostat. Lower radiator hose has the thick spring in it. I’m using 1 gallon antifreeze and the rest water with water wetter. My timing is 36* total and idle set at around 900 rpms.

The car never gets above 183 when driving down the road, but as soon as I come to a stop, the temp slowly climbs up. I’ve never let it get above 210.

I do have a 1” gap between my radiator and shroud and I suspect that I might be recirculating hot air under the hood as opposed to pulling max air flow through the radiator.

1) Do you think the gap between the shroud and radiator might be causing recirculating hot air flow? Pics attached.

2) is there a shroud out there for a mechanical clutch fan that will close this gap on a Champion 4 core radiator?

 

[CCKen]

Hi Cory,
We have a radiator that your stock shroud should fit closer.
Take a look at our website : coldcaseradiators.com

 

[Ccas]

You are absolutely losing a lot of cooling potential. Not only are you pulling in hot air, you are not creating the best suction affect. Normally the gap isn't too bad and weatherstripping could be used but that cap is very big.

Compounding the problem is the 4 core aluminum rad. There's a lot of turbulence created trying to pull air through that big of a core with the 3 gaps between each core. So with a 4 row aluminum unit, it's especially important to get maximum cfm pulling through.

Since that radiator looks pretty new, you may want to consider getting champion's shroud and fan combo.

 

[Ccas]

Also, have you tried to mount the shroud on the inside of the rad brackets? Maybe you could modify the shroud or use spacers in between the brackets and the shroud. That could move the shroud a lot closer to the rad and then you could use some type of weatherstrip to seal any remaining gap.

 

[69hemibeep]

I had a Champion 4 core in my Valiant and had the same problem. I went to a three core of another brand and solved the problem its hard to pull air through that thing.

 

[i_taz]

More isn't always better... My 440 runs a 22" 3 core Brass radiator from OER using factory shroud and fan with a Hayden 2947 HD clutch set up that looks and works perfectly...

 

[greatscot3]

Hey all

I've got a 22"x4 row champion radiator with a dual electric fan shroud for the radiator.
Does anyone here know what U-clip or kepnut would work to secure the shroud to the radiator?
Bolt size, and reach info for the U-clip would work great but I haven't any idea what to use.
Additionally, whenever I ask the people that sell the shroud and radiator, they haven't a clue either. It's like they have never done it before. One would really think they ought to know.