I never had any luck with the aftermarket fans. I had twin Flexalite fans and they didn't come close to cooling my engine. I bought a fan for a Chevy HHR ($50.00 through RockaRock Auto) modified it to fit my 26 inch Champion radiator. My Dart now runs 190 degrees in traffic. Actually it runs a little warmer when driving down the road probably about 200 to 205 but it runs much cooler when I'm sitting in traffic.
My Dart used to run HOT in traffic (230°) and I would be rushing to get to the parking spot at the cruise so I could shut it down.
490 HP 418 Stroker
26" Universal Champion Radiator ( no trans Cooler)
Brassworks Water Pump
190 degree high flow Mr Gasket thermostat
Trans Cooler/oil cooler combo with its own electric fan.
The above mentioned fan is a Dorman direct replacement for a Chevy HHR. $50.00 brand new from Rock Auto.