66-67 Dodge Charger Source Guide

I once replaced the original fan in my Duster with flex fan and was able to spin the rear wheels after doing that. 'Course the original was bolted to the slant six and the replacement came with a 318 attached. LOL ;-)

In all seriousness, I can't see a flex fan offering a HP gain over a clutch fan. Those clutch fans have a lot of slip in them, not a big drag I wouldn't think. The flex would be a gain if you were running a solid direct steel fan I'll bet. I bought a new thermostatically controlled viscous clutch for my car and it cycles nicely. You can hear it engage when the engine is hot and back off when the radiator cools down after the fan has engaged for a while. The thermo clutches have that little bi-metal spring on the front that looks like a watch spring.

Get a viscous fan from Mopar performance. Here is the Jeg's listing --312-P4120758 Viscous Fan Package $95.99 The best thing for a Mopar.

Try P/N 2863215; this was the original maximum cooling fan (7 blade). As it was max cooling, it was used with a fan clutch.

With all the discussion on A/C cars and if they had clutch fans or flex fans. I had my clutch go out on mine today on the way to work and Terri got me a new one with lifetime warranty from Autozone. It is made by TorqFlo, Part # 922408. This is the heavy duty clutch. The also have the standard duty clutch in stock. Cost was $54.00. Other part #'s listed as this being a replacement for is as follows:

Hayden: 2747
Four Seasons: 36956

The standard unit only had a one year warranty and was $30.00. Figured it was worth the extra $20.00 for the lifetime warranty.

Fan Shrouds

If your car had factory AC or factory max cooling package, then yes, it would have had a shroud. This mainly applies to the 26" radiators. There have been a few 22" radiators with shrouds, but good luck finding one, they ain't cheap. Also, if your car would have had one, the radiator would have studs for mounting it on the sides of the core