cooling fan

[str8muzick]

i have sbc 400 in a 83 pontiac gp what car can i get a dual fan assembly that fit exact or with little modifications

 

[85GPLef41]

I've read about Dodge Intrepid fans working as well as F&B body GM cars and Lincoln Mark VII fans if your willing to do same fabrication. I am also looking to do that upgrade soon. So who has done this?

 

[supercrackerbox]

A friend and I just installed a Mark VIII fan on his Malibu, and that fan is a BEAST. I'm told it's rated at 5000 CFM, and I believe it. Left running, the 305 never reaches operating temperature, and the fan all but drowns out the sound of the engine.

Luckily, the 454 goes in next week.

Installation Notes:

1. It's not a direct bolt it, but since these cars never came with an electric fan, then none would be. The fabrication is only as tough as you want it to be- meaning it just depends on how good you want it to look. The fan shroud itself is almost exactly the same dimentions as the stock radiator core.

2. 10 gauge power and ground wires, a heavy duty relay, and a 40-45 amp inline fuse are a must. This fan pulls some serious power, do NOT skimp on the wiring unless you want to burn it to the ground. 16-18 gauge wire is adequate for the switch wire, since the relay only pulls a few miliamps to close the circuit. This would apply to any electric fan installation.

3. If you're still running your factory rated alternator, it's time to upgrade. This Malibu for instance is a zero-power option car, and only had a 60 amp alternator. If the fan is pulling 40 amps, that doesn't leave enough to keep the battery charged, especially with the headlights on. A 100 amp alternator was swapped in, and all is well. This also would apply to any electric fan installation.

 

[85 Cutlass Brougham]

If you go with the Mark VIII fan setup, I would suggest running it off a thermal fan switch in the block. Use the thermal switch to run the ground side of the switched portion of your relay, and use a ignition on switched positive to run the positive side of the switching part. For the positive power to the relay, run your 10ga wire off the battery, or off a terminal block off the battery. I would also consider using a fusible link instead of a normal fuse, unless you get a big fuse block that is intended for a decent audio amp. For a relay, try to use one off a Mark VIII. In fact, try to salvage as much of the fan harness as is possible from the donor Lincoln. Those little Bosch DIN relays that everyone uses for their circuits simply won't cut it here. They are only rated at a 30 amp load. I would also wire in a dash switch that would let you pow the relay on when the car is off so that you can cool it at the track. You may need a switch that lets you ground and power it if you do that though as the TFS would shut the fan down when the engine was cool enough.

I will also add that a good pusher fan can be had off a Mercedes Benz 450 SEL Type W126. I run one of them on my AMC and it solved a lot of cooling issues.