Colling fan delima
 

i can't make up my mind , please help.
i have a 49 chevy p/u with a 4.3 V6 with a after market Speedway radiator, i need to decide on the fan. i am leaning towards a mechanical fan, i know the electric fans more common, but i am trying to go without all the wiring involved. my concern with the mechanical fan is the freeway speeds and overheating. should i put a fan clutch on it also, this is not a daily driver, more of a grocery getter, sunday cruiser etc. any input on any of the options is appreciated.
thanks

Re: Colling fan delima
 

I have never cared for electric fans. Block the radiator. If sensor, relay or power source go out you are without cooling. Use a mechanical with a shroud and you will not have any problems with that part of the system.

Re: Colling fan delima
 

Cool, i like that answer thanks

Re: Colling fan delima
 

Did the 4.3 come with a factory electric fan? If so I would wire it back in. The computer will control it very well. If not you can always put a fan thermostat on it and go. I do not care for the old style fans anymore.

There are millions of cars on the road today with electric fans and have no issues. A stock 4.3 should never have a problem cooling with an electric fan. My 408 has no issues with one and it is in the 500hp plus range.. Drive it on the interstate, city and back road street racing.

Re: Colling fan delima
 

my project is designed to be with as little electrical as possible. i just do not want to deal with all the fuses relays. sensors, etc but on the other hand i want it to cool properly.
1- electric fan
2- mechanical fan
3- mechanical fan with fan clutch

vote 1 - 2 - 3

Re: Colling fan delima
 

I'm with OrrieG on this one... go mechanical if you can. I am sorry that I dont have the clearance to go that route.

it is just a great piece of mind.

Re: Colling fan delima
 

You most likely won't have any issue with cooling at highway speed no matter what fan you have. Most trucks that have cooling issues run at the desired temp on the freeway at 70 but have trouble with air flow at low speeds or at an idle in traffic.

I'd say the key with the mechanical fan is can you put enough fan on it to pull as much air as possible though the radiator and can you position said fan so it does the most good.

Fan clutches are designed to pull a lot of air when the temp rises or at low speeds and freewheel a bit at higher speeds reducing the drag on the engine from the fan. The same size fan with the same pitch blades and no fan clutch will put a lot more drag on the engine at speed. y

Still in some setups an electric fan (s) may be the most practical or only practical way to pull or push enough air through the radiator to effectively cool the engine. I may be running electrics on my 48 with the 292 simply because I don't have enough room to put a full size fan on it with the way the engine sits in it. I know that the little fan that is on the truck is going to be a wall hanger an maybe I'll make a clock out of it as it's worthless for moving air in my truck.

Re: Colling fan delima
 

As a general rule, a mechanical fan in good shape will move a lot more air than an aftermarket electric fan. OEM electric is going to be comparable.
Also, tech tip:
At freeway speeds, the air blasting through your grill is moving faster than the fan will move it anyway. If you overheat at freeway speed, you don't have an airflow problem (unless the radiator is blocked) you have a water flow issue.
Around town, you need the airflow help from the fan.

Re: Colling fan delima
 

Highway speeds and computer controlled electric fans. They turn off over 40mph on most vehicles.