Fellas, I'm seeking some info regarding pushing and pulling fans. I would like to know if there is a difference in output between the 2. I've heard that most common type of fans are puller and that pusher fans lose about 20% of there CFM. How true could you guys say this statement is ?

 

The only pusher fan I've ever seen on a rotary is an auxilliary fan of the TIIs that is an assist for the ac, if that tells you anything. Youwill always get more flow pulling air through a radiator than pushing, mostly because of the shape of the shroud.

 

the fan i used in my 808 i'm sure was a puller. but with the combination of the 13b, along with an rx4 rad, there wasn't enough room to put the fan between the engine and rad. i put it on the grill side of the rad and wired it to blow thru the rad. i had no problems what so ever with it running hot.

 

Puller fans work better.

 

I dont disagree with this but , shouldnt a good fan push enough anyway? I have always heard that after 35 mph a fan is really useless anyway because you are flowing more air then a fan can pull. Is this not correct? I might be way off here but thats what I always heard.

 

Above a certain speed, say 35 or 40ish, a clutch fan doesn't really do anything. Compare that to a pusher fan which always sits in front of the radiator. It's always a restriction regardless of forward speed.

 

Ok, here's the result from this little mod. 1ST I searched for a fan that will fit the measurement of my Rx-3 rad. I found one through Summit Racing. It's a 10" fan that flows 2350 CFM from Perma Cool. So, I received the fan today and immediately installed it as a puller as recommend for optimal performance. Now, everything is installed and the engine stays right around 160*. I even let it idel for a while and it went went up 5-7 degrees in temperature. So, at the end of this day i was a happy rotorhead ! Thanks for the heads up fellas..!

 

Cool! Looks like I wasn't full of hot air. Sorry for the puns.