Electric fans installed into and 8.1 truck

tbyrne · June 13, 2003

I installed a set of Flex-a-lite 290 fans into my 2002 Silverado HD with the 8.1 motor. This kit comes with universal brackets so you pretty much have to come up with a way to mount the radiator.

I bent two of the brackets so they could be mounted to the top of the radiator support and then hang the fans from there.

After that I used some plastic strips from B+M to attach the fans to the radiator. I don't remember the part # for these but I can get that tomorrow.

Trucks with the Allison transmission have a seperate computer to control the tranny. This is mounted on the driver's side of the fan shroud. This will press up tight against the fans. I tried a few different locations but it was starting to become in PITA so I figured the stock location would be the best choice. I tried out part of the cover so it would go around the bracket and then mounted it leaving the two 10mm bolts a little loose. I also tied the bottom of the plastic cover back away from the fans with some straps. I might come up with a better way to do this but it's working pretty good.

While I had everything apart I also installed a ported throttlebody and throttlebody spacer. Did some driving that might and found that I gained close to 2 MPG. This truck gets thirsty with some of the mods and big tires so these were worthwild additions.

If anyone else is thinking about using these here are a few quick notes that will help your install. The fan controller needs to be connected to a wire that is hot when the truck is keyed on and cold when it is off. If you take the cover off of the fuse box under the hood and then lift up the cover that has the fuses in it you see 6 different sections. I used a wire in section 1 ( top left hand corner). Count two wires over from the right and 3 down. You will find 2 wires here. I used the purple one on the right. You also need to tap into the activation wire that goes to the clutch compressor for the AC. There are two wires there. I used the green one. These tips should help you get through the install in a couple of hours.

The Suburban will be getting a set of these next week.

Tom

2002 8.1 Silverado HD - Comp Cam, TOGs headers, Volant induction, Direct Hits ignition, 6" lift 18" wheels/tires + more

2002 8.1 Suburban -Intercooled Whipple supercharger, TOGs headers, Volant induction, 22" wheels/tires + more - 14.54 @ 92.43

www.tbyrnemotorsports.com

awdvkd · June 13, 2003

I hope you let us know more later. What did the setup cost and how long to install

Fishhunter911 · June 13, 2003

how did it help the overall performance of your truck?? I've think about the fan swap for a while now.

1BADHD · June 13, 2003

Can you feel a difference? Does it keep teh engine cooler? Where did you get the set up?

americanmuscleman · June 13, 2003

Very nice! Nice clean install too.

Just as an idea, if you want to "hide" that green wire that runs above the fans, you could pick up some 1/4" black convoluted tubing (like GM uses on their wiring harnesses) and hide that.

Love your trucks by the way!

tbyrne · June 16, 2003

We sell the 290s for $449.99. The install took about 3.5 hours. It would have been quicker but I was trying to find a good way to hang the fans and possible relocate the computer for the Allison. I could have the next set done in about 2 hours. The truck feels more responsive and I can definately tell it has more power when it shifts. The engine runs a little cooler but I wouldn't say that there is a big difference there. I'm going to install a 160 thermo next week so that should keep it cooler. Just has long as I can stay warm in the winter

I was going to hide the green wire but my convoluted tubing was no where to be found. I'll take care of that next time I get under the hood.

Tom

jdb1937 · October 27, 2003

Hi,

I always put in electric fans by flex a lite in all my vehicles now. I currently have a Ford Ranger 4.0 V-6, flex a lite M150 electric fan, 160 stat. The fan is actually one-half of what you have.

The 160 stat means your truck will run about 175 degrees water temp, if the stock cooling system is big enough to run that cool in the summer. In the winter it will run 175 all day- if you set the electric fans to come on about 170.

I have found that electric fans, even with a 160 stat, make great heat in the winter. And the truck warms up much faster, since of course the electric fan doesnt come on until 170 degrees, which is fully warmed up, and hot enough that you will not set off your check engine light. So know that not only will you have plenty of heat with the 160 stat- that you will get good heat faster with the electric fans.

In other words- to get good heat in the winter- i would much rather have a 160 stat and electric fans as opposed to a 195 stat but mechanical fan!

- All of this info is for Kansas weather- gets to a max of minus 5 in the winter.

Overall- your truck will run better, never ping or detonate, has much potential for more power as long as the cooling system is big enough to keep it cool, (ie advance the timing such as Wester's or other PCM mods) the engine will last much longer, and you will get plenty of heat in the winter with the 160 stat and electric fans. My .02 cents J.D.