Met with guys last night and opinions vary - What do you say?? My build is about finished (On my 289 motor in my shoebox ford) * Some say just use -- Mechanical Fan & Shroud * Others say; Elec Fan & to use a Shroud THE QUESTIONS - 1)How do you decide to use an Elec fan OR go with Mechanical & Shroud ? 2)Then what type Mechanical Fan is suggested? 3) For summer months, air cond use ,parade use --what works best? Guys -i just want to know once from guys who know Vs hearing chatter and opinions from guys talking to me.
My shoebox '49 Ford had a 302 with a 3 row copper/brass radiator. I ran an electric fan and she never overheated. My '52 Chevy runs a 350 and A/C. I run a 4 row copper/brass, triple pass radiator, shroud and mechanical fan. On a hot day with the A/C on, she runs at 180.
Electric fans only if a mechanical and shroud won't fit or you are trying for high et. That is if you can find a heads up race. Stay away from flex fan blade. You'll get opinions and highly effective arguments for both though.
keep it stock looking with a mec fan and shroud.if you need more cooling after its finished ,add the elec one .in my opinion ,motors look naked and unfinished without the fan [mec] and shroud.
Mechanical fans work just fine with a properly constructed shroud. The OEM got away from them to make engines more efficient. Even with a thermostatic clutch, the mechanical fan will always put some amount of drag on the engine. If it's any sort of period themed car, mechanical is your only choice...
It really all comes down to personal preference, either one can work well if set up properly. I use electric because I live in Florida and like to drive my hot rod like a regular car, which means lots of stop and go driving in traffic. I like the control I have over being able to flip a switch and having 2700 cfms of air immediately going through the radiator. But just do what you feel is right and don't worry about the other side. Don
I like the mechanical fan, and especially the "look" of old school small block with the fan....I use a flex fan that I carefully added more curve to the blades, no shroud, and have no problems at all. Sitting in traffic on an 80 degree day it stays in the 200 range. Moving on the highway, hovers in the 170-180 range.Now I have yet to use it in the heat of Florida summer, so time may tell that I need the shroud.
electric fans are for puss--s don't be a puss--. If you can't get it to cool with a mechanical fan ask for some help. Something is wrong. Electric fans are a cop out. It may be easy but they sure are ugly and not traditional. I'll always remember the Nats in 1980. Every day was above 100* I went through the manufacturers building twice and both times there was a line of people trying to find replacement electric motors so that they could get back home. No thank you!
Friend of mine tossed his belt in the burnout box- went 3/10s quicker than his best time ever. Alternator, water pump, and fan - combined engine drag on a dedicated race car. So he decided it might be better to get electric Fan & water pump, smaller alternator and bigger battery. Big money just to change the dial in 3/10. Yet to see how it runs. The transverse mounted FWD platform led to wide spread electric fan usage. It was out of necessity in that case.
either will work but alot of guys overlook how much air there pullin thru condensor when a/c is on just because your motor runin 180 doesn't mean your condensor is runnin too hot witch in turn brings up head pressue on a/c ie. blown freon line leaks and hard on compressor
a lot of it has to do with the radiator. Aluminum, no problem with mech. fan/shroud combo. Multi-core radiator-thick-now you've got to consider if the fan will pull enough through it. Same with electric type fans-if electric go Spal only-best one. Combo with both of 'em works for me. cooger
Use a quality made mechanical steel bladed fan,,engine driven fans in hot rods have received a bad rap in the last 20 years because of the flimsy aluminum fans that obviously made to look good but do not cool. Buy a good fan and you will be happy,,,I have this fan on both Deuces and the boss lady's '54 wagon. HRP
Looks aside, electric fans make more sense than engine driven mechanical fans. Fans create additional airflow through the radiator. You need additional airflow when the car slows down or stops and natural airflow reduces or stops. Mechanical fans also slow down at low engine rpm or idle - just when you need the most additional airflow from the fan. Electrics provide full flow regardless of engine rpm so they work better at idle. That said, all electrics are not the same. Get a good OEM fan like a Lincoln MK VIII, Taurus or Volvo and run it with a shroud so that it draws air through the entire core not just the circle of the fan and use a 75 amp relay to power it with 10 ga wire. Also mount it as a puller behind the radiator because the efficiency is dramatically better than a pusher.
Not EVER , not one single time ever have I seen an overheating problem caused by a mechanical fan. But I've lost count of the electric fan caused overheating conditions. Issues in the wiring, grounds, relays, diodes, thermostatic switches, motors, bearings will cause you overheating problems. Last one I saw was a 12.00 relay turned into a 1200.00 head job. Another OT ride melted the relays in a "Kit" twice. The stupid core inserted thermo bulbs are complete junk too. Use an electric only if you have to.
I had similar issues with my 51 Ford with 351W motor. Tried pusher electric puller electric various thermostat temps and finally got a combination that cools. 195 thermostat, 17 inch mechanical fan, good fitting shroud and good fitting gasket between rad support and hood. At least part of the problem was air taking the easiest route and going between the rad and the hood and out the 196 louvers in the hood!
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