news fans with or without shroud

Will you be reusing the old radiator? Upgrading the stock fans is highly recommended.

I'd say if you run with two pullers, then USE A SHROUD!

The shroud increases the fans abilities by a LOT. So on that 100 degree day when you're stuck in traffic, you won't have any probs. Fans and shroud are behind the radiator so when not running, the air still hits the fins and allows the radiator to work normally.

Also, newer fans from Spal are flatter, and lighter, and are very nice. They'll have a fan (or pair) that'll fit your needs.

Schrouding was the solution for me.

Thanks,

I plan on using the stock radiator.

Any suggestion on good source for fans and shroud assembly that will fit with the inlet and outlet tubes in back of radiator?

I don't think I've heard of a shroud for the stock radiator.

To use a shroud on a stock brass radiator, you must use some sort of method to hold the shroud lightly against the core. I once made a dual fan sheet metal shroud that used 4 tiny sheet metal screws into a flange surrounding the core. My current aluminum rad & plastic shroud uses home-made strap-clamps. The fasteners need not be structural since when the fan(s) are on, the suction created presses the shroud tightly against the core.

Second, you must cut the water pipe elbows off the rad and add in short sections of hose to extend the in/out pipes back about 2", so as to clear the shroud & fan bodies. Aftermarket Pantera rads do not usually have elbows, so in that case, two 90 degree 1-1/4" copper sweat-solder fittings with extension hoses on the straight stubs work fine & are corrosion proof.

Do NOT use tie-wraps to hold ANYTHING to the core! Nylon tiewraps are much tougher than either copper or aluminum radiator tubes and will quickly saw through them with vibration, scrapping the radiator. Why some suppliers include these dangerous things with their shrouds, I have no idea.

I used a Flex-A-Lite FLX-240 for my stock radiator. It's a pusher fan setup that installs in front of the radiator. They blow a total of 2500 CFM.



The stock Pantera fans blow a total of just 600 CFM; it's quite an improvement.

The fans sit in a nice shroud with a thick rubber gasket that cushions the shroud against the radiator. Just remove your stock fans and it slips in like it was made for it. No need to fasten it to anything, just slide it in and it wedges nicely into place. The very top of the shroud will be about 3/16 of an inch above the radiator when it's in place, but it's fine & the metal cover that covers the fans (the one with the 2 Phillips head screws that covers the top front of the radiator) fits with no problem. The bullet end wire connectors even plug into the factory connectors.

SPAL fans I think are known as one of the best brands of fans. They make them in all shapes and sizes and would have what you need for sure.

SPAL fans have awesome CFM. However, I have run into issues with their high amp draw. Specifically melting relays (Bosch and Narva) and encouragement to run higher amp alternators that create more drag and belt squeal (more so when running a flat firewall kit). If memories serves they draw about 27 amps each depending on size. Perhaps twice the amp draw of others with slightly less CFM. No free lunch.

Thanks for current info
I had the same concern as to what would happen with both fans, A/C and lights on.

I thought of needing the 100 amp alternator. Didn't think about extra load on pulley drive.

Anyone else have comments about the very high current draw

Tnx

Have you seen Pantera Electronics? Jon recommends these SPAL fans. I installed the Pantera Electronics fan controller and the recommended fans along with the GM12Si alternator. All works well.

Steve

Thanks steve

A couple of questions, you have a new radiator, did you have to tilt forward? I am using original radiator

Also, I see no shroud. I went to site and said no shroud needed.

So I assume it was tested with and w/o shroud and a shroud didn't make a difference. Is that correct?


Steve c

My experience with SPAL fans was good. On my last car, which I installed a big turbo kit, there was NO ROOM whatesoever, and the Spal fans were the only ones to handle the heat after we made mods to gain clearance from the downtube.

The shroud increases the effectiveness of the fans a LOT, like 2 or 3 times better I would guess. With a proper shroud, then ALL the radiator area is getting air sucked through, not just two circles worth of area.

Not sure how that affects things when the fans are NOT running, because then parts of the radiator are being partially blocked (not completely because the shroud Does stand a bit away from the radiator, which Will still let air flow across the entire radiator) but at least on my old car, where it was critical, the shroud made the difference between working, or not working. The difference was HUGE once we installed the shroud.

quote:

Originally posted by JTpantera:
SPAL fans have awesome CFM. However, I have run into issues with their high amp draw. Specifically melting relays (Bosch and Narva) and encouragement to run higher amp alternators that create more drag and belt squeal (more so when running a flat firewall kit). If memories serves they draw about 27 amps each depending on size. Perhaps twice the amp draw of others with slightly less CFM. No free lunch.

One thing with big fans is, using stock Pantera wiring may limit your cooling. There's about 5 or 6 extra feet of extra wiring folded into the front wiring loom under tape and the more wire & connectors, the less electrons get to whatever device is connected. An odd characteristic of electric fans is, a drop of only 1.0 volt to a motor may reduce the fan speed by 25%, so that advertized 2500 cfm airflow becomes 1875 or even less. When I analyzed several fans for their airflow in our '72 Pantera, that's what I found. The simplest way to check this is with a mechanical tach on the electric motor shaft, or simply connect the fans directly to the battery with jumpers. If the fan speed or noise increases noticably with direct connections, further checking of your wiring will likely show less than an optimum 13.2vDC going to the fans thru the stock wiring.

When I started checking fans & motors in the '80s for our car in trying to sort out cooling problens, I borrowed a $500 portable anenometer from the heating/AC maintenence men at the company I worked for. 20 yrs later (2012) I bought a Chinese airflow meter off the Internet for $29. My mechanical tach is a Stewart-Warner unit meant for checking machine tool shaft speeds with no electric hookup needed.

I also found that s-blade fans move no extra air over identical straight-blade fans; mfgrs use s-shapes 'cause they're quieter. More blades at the same speed do move more air. I also found that with sucker fans, spacing the whole shroud an extra 2" away from the rad core increases airflow by 5% due to less turbulence inside the shroud. The simple shroud extension I made covers 100% of the rad core with no open areas. Spacing the fan motors such that fan blade tips are positioned out of their large holes by 1/4 the blade-tip width also gives more airflow.

I have the front mounted Meriah (sp) pusher fans, which I measured at 4 amps each, steady state. I also had a sucker fan behind the rad which had the thin "pancake" motor; that one took 11 amps. That's the trade off - the thin motors help with your mounting space, and are lighter, but take more electrical power. Rodney