mechanical fan vs electric

[89Bronco58]

i have an 89 xlt with a efi 306 **...more power than the stock 302 of course, but today i ripped the stock fan off it because the clutch once again got stuck on the fan, and i replaced it with a big electric fan, relay, switch...all the correct way..i heard this will give you a few HP and some better gas mileage...anyone ever done this, and or gained anything or experienced problems???

 

[Seabronc]

If it is hooked up right, it is definitely an advantage. It removes the fan load off the engine and takes the HP that it uses for the fan and leaves it for moving your truck around. On my truck the fan runs less than 1% of the time the engine is running. Even on the hottest days around here, (95+) with surface temps in the 120 to 135 range it only comes on when I'm traveling below 35 MPH. On cooler days (temps in the 65 and below range), it doesn't come on unless I'm setting at a traffic light for a few minutes. Right now with temps in the 80's it comes on when I stop moving. You probably won't see phenomenal changes in mileage, more likely in the 1 to 2 MPG range, but with a Bronco that is around 10%. I was convinced to do it after reading about the conversion on the Ford Muscle Magazine site http://www.fordmuscle.com/TechDepartment/cooling.php

How about some pictures of your installation? Mine are at my Supermotors sight listed below.

 

[89Bronco58]

good i hope i get soem better mileage, thing i like most is that you dont hear the fan when you rev the engine up, my fan clutch was going bad anyway...only thing is that i hooked it up with a relay and whatnot, but when i turn it on my guages go crazy, they go about 1/4 of the way up......

 

[Seabronc]

If your fan draws like mine, you need to upgrade your alternator to a 3G system. You are putting a load on the regulator that the old system has a problem supplying. I have a 130 Amp alternator in mine. Even with the new system my engine lugs down when the fan kicks on, (100Amp start current with a 33 amp run current), if the engine is near idle. I can solve that with a throttle kicker solenoid, but just haven't put the time into it yet.

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