Big block cooling article question

[Orangedog70]

A while back Motortrend / HotRod had an article;

Mopars Need Extra Help With The Heat—Here’s How To Fix It! What's the part number for the fan clutch in this article? I tried emailing them several times with no response.​

 

[Ricks72Chlgr440]

For very tight clearance between the radiator and water pump snout the Hayden 2947 is the ticket. I don't agree with the writer that the mech fan is more efficient than elec fans. At very low speeds or stuck in traffic in hot weather airflow thru the rad is at minimum with mech fans and is where the proper elec fan setup really shines.

 

[Orangedog70]

A while back Motortrend / HotRod had an article;

Mopars Need Extra Help With The Heat—Here’s How To Fix It! What's the part number for the fan clutch in this article? I tried emailing them several times with no response.​

Ok, thanks.

 

[540HemiCuda]

Here is an old thread that discusses the Jaguar fan clutches. The 2947 is what I use with a cut down aluminum Dodge truck fan. It moves a LOT of air at low engine speeds. https://board.moparts.org/ubbthread...vy-duty-low-profile-fan-clutch-jag-style.html

Also check the bypass hole in the water pump housing underneath the thermostat. It is usually too large. Drill and tap it for a brass pipe plug that you drill a smaller hole in. As small a hole as will still allow the thermostat to open properly. Otherwise, it allows more hot block water to circulate right back into the engine.

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