I have recently discovered the fan holy grail.
It’s made by Spal and is used in the 2016 – 2020 Camaro & some 2016 – 2019 Cadillacs. The
GM part number is 1581927 (15-81927) Radiator Fan Assembly and can be found in your local junk yard for cheap or at RockAuto for $287 (as of 12/15/23).
This is a 19”, 850 watt, brushless, PWM controlled fan that pulls air through the radiator, AC condenser, and grill of my ’67 bird like nothing I’ve ever seen before. There are some other models out there, like the 650 watt version for the C7(?) Corvette and I think that VW &/or Volvo has a dual fan setup, but this is the one I used.
The fan is 19” diameter, plus the frame, and the Firebird radiator has a 23”W x 16.85”H core so I had to do a bit of fabricating.
Fortunately, the frame was the perfect width to fit the 23” wide core although I did have to cut a couple of the protruding mounts off of the sides to clear the inlet/outlet.
I trimmed a piece of aluminum angle to fit the top to be a mounting bracket. (I polished this to a mirror shine later on.)
I installed some of this foam tape to prevent chafing and seal the fan frame to the radiator.
The motor adds about another inch, but it’s still and extremely low profile fan when compared to brushed fans.
Since the fan is so much taller than the radiator core, I added a plate to the bottom to seal thing up. It hangs down about 5”, but doesn’t interfere with anything and buts up to the back of the lower air baffle.
I think I had a piece of ½” square tube filling the gap between the radiator & fan frame, but a piece of angle would also get the job done.
This fan needs around 70 amps running at full speed so 8awg wire and a 90-100amp fuse is required. If you want to use the factory type plug, you can find it on Amazon for about $25. Search “GENUINE NEW Replacement Connectors, Terminals and Seals for Spal Kit 30130628 Brushless Fans”
A cheaper alternative would be to find one in a junk yard.
Since this is a brushless PWM fan, you will need a PWM controller. I went with the “Widget Man” BRUSHLESS PWM VARIABLE FAN CONTROL from eBay for $65. I had a few problems and the seller, “GKGoodCheapParts”, provided excellent customer service. The controller is small at about 1.25” square, but is easily programmed to come on at whatever temp you want and reach full speed when you want.
The problem that I had was that when I turned on my AC, it spiked the circuit, releasing the magic smoke in the PWM controller. The controller has a “Force On” terminal that will force the fan to run at full speed or will add 50% speed to whatever it’s currently running, depending on how you set it up. This terminal is normally grounded and when the ground is removed, the fan ramps up speed. If you’re not running AC, you could ground this terminal through a switch so when you threw the switch (opened the circuit) it would act as a manual override for the fan. If you are using AC, I recommend that you use a relay to lift the ground. …Just in case.
The first relay in the pic below creates a circuit that isolates the controller from the AC compressor, and any 12v+ source, and the second relay provides for a manual override to force the fan to full speed.
Here are a few different angle of the install. For reference, there was only about 5” between the radiator & water pump pulley.
