Thread: Pusher or puller fan(s)????

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ok, here's the deal... I prefer mechanical fans, but the guy I'm building the '36 Plymouth for prefers an electric fan for cooling... His car, so that's what I'll use...

The engine is a 5.7 Hemi with the 4 speed automatic overdrive and has a Vintage Air unit. Vintage Air suggests 2,000 CFM as an absolute minimum for the fan. The condensor is of course mounted to the front of the radiator and measures 14" X 20", so not a lot of room for a pusher fan. If I use a puller, the radiator itself measures 15" X 21".... Keeping the CFM requirement in mind, wondering what suggestions you guys might have as to which would offer the best cooling.....??????

Oh yeah, I'll also be installing a separte transmission cooler with fan, too. The radiator does not have a trans cooler built into it, so no extra air flow needed for that....

Thanks for the help!!!~!

Dave at the car show this weekend, one guy I talked with had a pusher electric fan setup. He said he never has problems with it getting hot even sitting in traffic. Most of the others that were using electric seemed to have pullers. I like the front of the engine clearance for the pusher fans. Yet I don't have any experience with them myself! I will have to go electric pusher on my truck due to space issues, so I'm hoping to pick up info from this thread too!

It's generally accepted that pullers are more efficient, especially when used with a shroud that covers the entire surface of the radiator core. A SPAL is something like 2700 cfms, and they make a slimline version that I have had good luck with.

I would have suggested that you use a SPAL 16 incher, but you only have 15 inches to play with, so instead I think two 10 inch ones , staggered, on a shroud would work well. From what I understand, two 10 inchers do not equal a 20 inch fan in efficiency, but they do move a fair amount of air.

The shroud should be made so that it is about 1/2 inch off of the surface of the fins, so that air can be dragged clear across the core. Either aluminum or sheet metal can be formed to the shape you need, then you can cut the correct sized hole(s) for the fan(s).

Don

Thanks Don. I've used Spal in the past, only had room for a pusher on that one.... With a bit of overhang, I could use a 16" puller.... Would only be 1/2" wide on either side, barely the width of the radiator frame.... Think a quality 16" puller with a well designed shrould would be the way to go on this one?????

i have two 10 inch spal pusher on the 50 with the blower i hade no other way to go .they are very loud .pullers do work better .i would look at the bone yard for fans like a gm front wheel drive car fan you may get a better fan then a spal

Thanks Pat! Anything in particular too look for that you know of??? Got to go to the U-Pull-It Thursday anyhow.....??????

Originally Posted by Dave Severson

Thanks Pat! Anything in particular too look for that you know of??? Got to go to the U-Pull-It Thursday anyhow.....??????

the old grand prix are the ones the off road guys use

Yep. I never thought of the only 1/2 inch overhang, plus I'm not sure it it exactly 16 inches anyway. My first experience with a SPAL was on my Jeep that I had the 5.0 engine swapped into. I had been using AutoZone specials, and the truck always got warmer than I would like at lights. I put a SPAL on it and immediately my cooling problem when away. The cfm's it puts out were much stronger than the cheapos I had been using.

We made the shroud for Don's T and mounted a SPAL on it. All we did was bend up some 18 gauge and cut the right sized hole in the middle. Took all of one evening to whip it up. I think that would work just as well for you Dave.

Don

i did work for becool i made up there stands they wanted to have all there spal fan on one stand .so they could turn them on at shows .i told them never turn all the fans on or it could fly a way

Got a brake and a slip roll at the shop, so the shroud is not a big deal.... Fun to play with and do some of that creative stuff!!!!!!

Originally Posted by Dave Severson

Got a brake and a slip roll at the shop, so the shroud is not a big deal.... Fun to play with and do some of that creative stuff!!!!!!

is that stuff going to tx

Originally Posted by pat mccarthy

is that stuff going to tx

But of course!!!!! (along with the English wheel, planishing hammer, and the rest of the goodies) Hope things go right and I can start putting the shop up next winter!!!!!

As pops said that Spal 16 inch puller is hard to beat. I am also using a "fan controller" from speedway that I can program to turn the fan on and off at various temperatures. the combination of the fan, custom built shroud and controller keep my rod at 180 even in 95 degree heat. Don Jr.

I use a Cooling Component Fan in my 36 Dodge w/ a BB as a pusher ..The best to buy.. Also I use a B&M remote trans cooler under the running board.

http://www.coolingcomponentsinc.us.c...p/shrouds.html

Hi Dave,
On the 36 Chevy that I'm building, I put on 2 - 10 inch Spals Puller fans in a shroud. I went with the two fans rather than one larger one because the total surface area calculated to be more with the two fans rather than the one.

A friend pointed out that the shroud should not have any chance for the air to "Leak" around the shroud but rather ONLY pulling it through the radiator. Air, like water, will find the path of least resistance so it is critical there are no gaps on the sides of the shroud. I'm happy in how this turned out cosmetically. The true test is when I get the LT1 fired up and having the computer control the fans on temp range. As the fans are set up at different temp ranges.
Jerome