Just got my 327 running in my 51 chevy. got is timed and running good. for the most part it runs at 175 until I get into traffic then it likes to creep. Since the motor is new I am a little paranoid and thinking I might add a electric radiator to it The mechanical fan is a factory 7 blade and I have a new 2200 cfm Spal fan in my parts stash that i am thinking of putting on a toggle switch on the grill side of the radiator. It is a puller (pulls air from the engine compartment out towards the grill. ). If i remember you do not want to run a mechanical with a pusher (push air towards the radiator) as it can cancel each other out. Is my memory correct, the right way is to run a puller if I have a mechanic that is pushing on the engine side.. (what type of relay should I run?) I can not find any instructions for the fan.
If you do not have a fan shroud I would address that first before adding a crutch. Make sure that all the air the fan moves get pulled through the radiator. Also, I believe Chevies of that vintage have shrouding behind the wheels to the sides of the engine, if these are intact they need to be removed for a V/8. They will block the exit flow from the engine compartment. ~Alden
Cadzook, I agree the fan would be a crutch until I could get around to building a shroud. are you talking about the lower panels at the lower back. I have never heard of this but it makes sense..
The panels are next to the engine, and behind the front wheels. On the six cylinder they helped air movement, I think, but with a V/8 they form a restriction. ~Alden
If I am reading what you wrote correctly, you are backwards in your thinking. A puller goes BEHIND the radiator (between radiator and motor) not in front of it. If you did that it would be trying to push air out the grille, which is backwards of what the normal flow should be. Either replace your mechanical fan with that SPAL puller (which is a very good fan by the way) or put an auxillary PUSHER fan in front of the radiator to shove more air through the core. I would just put the puller behind and call it good, I have on of these on my 27 and it keeps my 331 stroker cool with a severely chopped radiator, and I ran one on my 23 and it kept a 350 at 170 with a 190 thermostat. If a car runs cool going down the road but comes up in traffic, it is air flow that is causing it. IE, you are getting enough from the movement of the car but not enough from the fan when sitting. As for a relay, put a 40 amp relay and a toggle switch and you will be good to go. Don
Don, you are correct.. I got my pull/push backwards.. spent the weekend on its first road trip and the car rode at 175 the entire time until we got into cruising that night and then the temps rose some (not critical but if it had been 80 degree plus it might have gotten over the 210 level).
Boones, I am sorry I did not catch what you had written in your original post. Don is correct. You would never want the fan pushing or pulling air out the grille. Both types move air from the grille through the radiator and out through the engine compartment. A pusher lives in front of the rad., a puller behind. Always blowing to the rear. As you can tell I am a firm believer in mechanical fans. A 7 blade fan with a proper shroud will move much more air than an electric. When space allows for it that is always my first choice. ~Alden
IMHO nothing cools better than a 7-blade mechanical fan. How hot is "it likes to creep?" http://www.jalopyjournal.com/forum/search.php?searchid=2774191
Its seemed better to my way-of-thinking, to create a low pressure region behind the radiator with a custom fitted shroud and a pulling fan, either electric or a mechanical.
Like Nancy Reagan said...just say no to electric fans. With a descent radiator and a pressurized system it should not boil over in traffic. If your vacuim advance is hooked up to ported vacuum instead of manifold vacuum it will tend to run hotter at an idle because it is so retarded compared to what the factory intended If you are just scared because you can see the temp above 210 don't ever put a temp gauge on a modern engine. That's why there are no numbers on a modern temp gauge on a new car. All you mentioned was the temps on the gauge. No boiling over or steam? Engine temps vary so don't get paranoid. They've been putting theses engines in these cars for 45 years long before electric fans became the lazy way out.
We could take evey worthless electric fan ever produced for the street rod market and dump them in the deepest part of the Pacific as far as I'm concerned! A pusher fan on the front probably doesn't make enough CFM to "cancel out" the effects of your engine driven fan, But it does do a great job of blocking quite a bit of critical core area. Build a shroud and you'll never have a problem again.
On my F-100 I built a shroud out of fibergl*** resin and an old Kurt Cobain t-shirt. UGLY!! ...but ran cool here in Phoenix. Mechanical fan. "G'damn the pusher fan" that's funny right there.
Lazy? Sometimes there is no other option, and sometimes even a puller electric or mechanical is not an option! Given the option of a puller mechanical or electric I would always go mechanical, but if there's room for one there's usually room for another. I'd have loved to figure a way to run a mechanical puller, but with moving the firewall back almost 12" and sitting in the backseat already, I couldn't imagine moving it back even another inch or two to get a mechanical puller on the pulley. If I went back any farther I'd be notching my windshield to clear my scoop!
I read that, but I'm just too lazy to comment. What do you think the minimum distance is that's necessary to mount a good, reliable mechanical fan? (Distance meaning from the water pump mounting flange to the radiator fins).
Depands on what fan you want to use. Most aftermarket ones are as flat going toward the front as possible and will fit with 1 1/2 "
I'll go more like 3/4" to 1" if I can get it. If you are using a clutch fan, usaully more like 3"-4". But a flex fan is still loads better than an aftermarket electric.
You actually don't want your car running too cool. You want it running at a hot temperature that isn't in danger of boiling over. I've had two F100's (a 65 and a 66) where it was actually a chore to get them running hot enough.
What brand(s) of flex fan looks traditional? How about one of these? Click here: Flex-a-lite 1617P - Flex-a-lite Race Fans - Overview - SummitRacing.com
I have 2.25 inches between the radiator and the fan mounting flange on the water pump ( SBC350 ) . I use a 4-blade GM truck fan mounted directly on the pump ( no spacer ). This puts the blades about 0.75 inches from the radiator. I'm running a Walker radiator with their plastic shroud . The fan blades are about 1/3 inside the shroud,2/3 outside. Cooling is great ...absolutely no issues with overheating.
I'm running the 7 blade 17" Flex-O-Lite trimmed down to 16 3/8 in blue/ stainless but black'd out. Looks Ok to me. Oh and it's fully shouded. My cooling situation was challanging but I have licked it # 1817
Boones ... You know I live in the Hot, Muggy, high humidity SOUTH ... where 2 or 3 weeks of 100 plus days are normal in the summertime. I agree ... Throw ALL the electric aftermarket fans in the trash ... Both of my Deuces ... run 180/185 all the time. No problems and YOU KNOW that I drive my cars a lot. Build a shroud and be done with the issue.
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