Electric fans modification 5.7

[Chevy_Finatic79]

I want to by-pass (get rid of) my water pump mounted fan and put electric fans on my 85' C-10 T.B.I. 5.7.

I read somewhere that dual side by side electric fans can't properly cool a 3 or 4 core radiator but which I think is Bull because my buddy has a factory 1 electric fan setup on his camaro with the same motor and it never overheats and his radiator is a 3 core.

I plan to have the A/C hooked up as well and dont want to run into any overheating issues.

the reason I want to switch to electric fans is I heard you loose 20-25HP thru the water pump mounted fan "I dont know if this is true but it makes sense since the motor would be doing less work without the water pump fan"

my plan is to scope the boneyard and bring home the biggest side by side fan setup I can find (maybe a 4.5L caddy motor fan setup). I was even thinking of getting a little single fan for my tranny line cooler and the A/C condenser that would mount in front of the radiator.

do I need something special to tap into the coolant sensor that triggers the fans to turn on?

has anyone out there ever done this? I could use some help or advice and what not to do's

[stumpuller454]

i`ve picked up a drop in unit from summit racing its made by perma cool, flexalite makes one too. they bolt in were the shroud is, has a power, ground and accesory "on" wire (which can be connected to A/C cucuit), is extremely easy install, has a module and a temp probe that installs into radiator and is adjustable for what temp you wan it to come on at. this was just an easy way out, got frustrated trying to figure how to wire and mount fans from other vehicles under the hood. and just as they say these are not for towing purposes, although i have, it doesn`t overheat but it does run warmer.

not 100% sure but they might make one for that application,...

[HardRock]

Not sure what brand mine is but sure seems to cool fast...I also put in a new Alum. radiator...but when both fans kick in it really sucks the power.

[gmctrucks]

I seen a dual fan set up that was on a big block for sell on ebay I would go with a dual set up why chance it and mess up your truck in traffic here in houston on a very hot day my temp will start going up but I have power pulleys I sure would like a four core radiator remember your friends ride has a three core that helps a lot I might someday go with a dual set up myself someday and if I was running a stock themostate I bet it would over heat bad im running a 160' themo because of my Hypertech chip.

[Nold Dog]

I converted my 1968 El Camino to electric fan. I got tired of replacing the short nosed water pumps (GM went to long nose water pumps in 1969 - much better design) - my El Camino has over 400,00 miles on it. First, I tried 2 fans side by side. One switched on by the key and the other switched on by the A/C and/or a thermocouple on the radiator. I made an aluminum box/shroud to hold the fans and it worked okay. But the electric motors kept failing. So......, I went to the wrecking yard and picked up a plastic fan shroud from a GM Fiero (it was rectangular and the height was perfect for my radiator) and a couple of electric motors. Almost all of the GM electric fan motors there were the same - just mounted in different plastic shrouds. Then I made another aluminum shroud the exact size of the radiator core with an opening the size of the Fiero shroud. I mounted the Fiero shroud with motor to the aluminum shroud, sealed up the cracks/joints, and mounted that to the back of my 3 core El Camino radiator. The single OEM electric fan keeps my El Camino cooler than the dual aftermarket fan setup. I believe this is because the second fan shroud sealed better. The dual fan setup had a big hole (for the second fan) in the shroud under normal driving.
Also, the OEM wrecking yard fan motor is working just fine after 5 years.

[leolkfrm]

do you have a clutch fan now? if so the loss is not that much. What are you doing that you might miss 20 hp?

[Chevy_Finatic79]

Originally Posted by leolkfrm

do you have a clutch fan now? if so the loss is not that much. What are you doing that you might miss 20 hp?

you ask that question like a 20 Horse Power gain is not noticeable???

if you were to suddenly loose 20HP you would surely notice a loss in performance.

If you take a 50HP motor and do a modification that adds 20 horse making it a 70HP you're telling me I wont notice any difference at all?

There are a couple reasons I want to eliminate the clutch fan:
1. the motor will do less work at the fan and have more power available to the crankshaft when I punch it (HP GAIN)
2. I want the cleaner "more exposed" look in my engine bay
3. In the future I wont have to finagle the belt around the fan and the shroud when changing the belt (Easier maintenance)

I was also thinking of a electric water pump to gain even more horse power

[Sneakysportsman]

I run dual Electric fans, have a sens in the radiator, manual on-off switch or they com on when the A/C kicks on. If they don't come on when the A/C is on your A/C will not be cool because there is no air flowing across the condensor.