I have never heard anything good about Flex fans. What is the general consensus out there? I'm strapped for room and I'm not sure the electric fan I have now 16 inch will do the job Cooling a mild Street 440.
Hard to improve on the factory fan. Sometimes there just isnt a better mousetrap.
VERY NICE PICTURES......BUT, "pulls more air at idle" means nothing.....how much air is "more air"? Quantify with a CFM number and at what operating RPM. Regarding the race fan application, what components are "not needed for a race application"? AND WHAT IS THE MAXIMUM RPM that is allowed b4 self destruction.Here are Flex a lites factory style 18" fans.View attachment 1167579
I appreciate that you want to show your expertise. There is "No" cfm per rpm for the factory fans either. The OP asked for some info on Flex fans. I appreciate that you are bored.VERY NICE PICTURES......BUT, "pulls more air at idle" means nothing.....how much air is "more air"? Quantify with a CFM number and at what operating RPM. Regarding the race fan application, what components are "not needed for a race application"? AND WHAT IS THE MAXIMUM RPM that is allowed b4 self destruction.
The whole point of a fan clutch is to limit the fan's RPM to limit the HP consumed at "race speeds" and have more HP available to propel the car. Refer to an excerpted fan law explanation below.
Fan Law 1 tells us that the change in air flow rate of a fan is proportional to the change in speed of the propeller. If the propeller speed is increased by 10%, the air flow rate will also increase by 10%.
Fan Law 2 tells us that the change in total static pressure of the ventilation system will increase by the square of the change in propeller speed of the fan.If the propeller speed is increased by 10%, the total static pressure will increase 21%.
Fan Law 3 tells us that the change in horsepower required by the fan to turn the propeller will increase by the cube of the change in propeller speed of the fan. If the propeller speed is increased by 10%, the horsepower required to turn the propeller will increase 33.1%.
Sort of self explanatory.....
Moral of the story......ASK FOR SPECIFICS B4 YOU BUY......
BOB RENTON
Bored??? Absolutely not. I believe the OP asked if flex fans were any good.....IMO....short answer....NO. With regard to the use of fans in general, the presented information is to help make an intelligent decision....take it or leave it....its up to you. But without accurate information its impossible, or nearly so, to make a worthwhile decision....about fans or just about anything else.I appreciate that you want to show your expertise. There is "No" cfm per rpm for the factory fans either. The OP asked for some info on Flex fans. I appreciate that you are bored.
Oh yeah, they eat power. Engine masters did a fan test to find out how much power they use. They tested the plastic "flex" fan I use, with a bunch of fan pitch, and it ate 25 hp. The fixed standard blade was somewhere around ten worse yet. Best was a factory clutch fan, ate somewhere around 10-15 hp.I thought the whole point of flex fans was, the blades "flex" and flatten at higher RPM thus eliminating drag and freeing up a little power....but you guys are saying they cost power? I've never used one, just curious..
Okeedokee!Oh yeah, they eat power. Engine masters did a fan test to find out how much power they use. They tested the plastic "flex" fan I use, with a bunch of fan pitch, and it ate 25 hp. The fixed standard blade was somewhere around ten worse yet. Best was a factory clutch fan, ate somewhere around 10-15 hp.
Some questioned their test methods, but I think they were close.
My fan probably eats that much, but it keeps my engine cool. THAT is its job.
An electric or two could probably save a few hp, but I would rather not have to deal with them on this car.