Cosmo Kramer

Well I am going to start looking at this now that the weather is getting warmer. Right now I have the stock S3 front electric fan with the factory hookup and the belt driven puller fan is removed. I have installed a 12" puller on the lower PS of the rad that I haven't hooked up yet. I also have a 16" pusher that came with my box of parts that I haven't installed yet.

I am thinking of installing the 16" and removing the stock fan and using the factory hookup, I figure this fan will be a lot more efficient. For the 12" that I have installed already I was thinking to add an aftermarket fan controller/rad probe, wire it to the hot post and adjust the controller to have it come on earlier then the big one. I think this should be more then adequate cooling.

Any thoughts?

antsmands

I have a 16in. str blade 1550CFM puller fan that I bought for another of my vehicles that I am going to try on my car. I am planning to maintain the original fan since it has only come on when I used the AC and add the puller to the system using the jump post and a temp probe that came with the fan kit in the top return radiator hose. My concerns are that 1550 is not enough since I seen most on this form talking about 2300+ cfm fans and the load on my stock alt if both fans are running.

antsmands

"Snakefeeder" on this forum was doing a fan conversion project but I havenot seen an update from him.

mark kibort

Yes, you need the 16" fan to move as much air as the stock system (with pulley, driven fan)
the front fan is useless without the puller to help it be more efficient.

jpitman2

I tried a modern 16" fan front and rear, but they couldnt control the temp well enough for my liking in 95F ambient. I (and some others) also think that the bottom temp sensor does not do the best job because of temp differentials across the radiator - hence going to top sensor as in 928motorsports product. I now have a dual SPAL11" unit in place, rated at 2780cfm, costs $204 from thefanman. These move a bucket load more air than the 2 x 16" did IMHO. Might require some mounting bracket fabrication, but I have retained the top inlet hose part on mine, so it looks stock. SPAL somewhere rates these at 10,000 life. They do a 16" single fan rated at 3000cfm, but it carries NO warranty, and is not sealed, intended only for racing use.
Pic is of the mounted fans before install. The holes line up with original shroud mounts. Its within a couple of mm top to bottom, and maybe 20mm shy of the right side, which helps to prevent fouling the auto box cooler pipes there. The plastic shrouds have the same rubber blow-open flaps as some of the other units available. The frame is just hardware store alloy angle - 1/8" thick L section on the 4 sides, with 1/16" L for the top bracket to mount it. Spaced 1/8" back from the body of the radiator to prevent any chafing.
jp 83 Euro S AT 52k

antsmands

Hey jp Thanks for the info. Post a pic so we can see your install!

Cosmo Kramer

Thanks for all the info guys, I am going to install the new fan at the front as well and see how it works. I may just wire both of them to the temp probe so they come on at the same time.

Imo000

One 16" in the front will be enough. It's enough for me and my temp. probe is non adjustable. Comes on at the last white line and within a minute, the temperature is down to half. I tried this on the hottest day with the engine heat soaked after a good full boost run. My fan is wired to run even if the key is out, this way it reduced the heat soaking of the engine. It onyu runs for a minute so drainign the batter is nto an issue. However I don't have AC and the condesor is pulled.

jpitman2

trying again to attach pic

Tampa 928s

Your air box is different, I have 4-Fans wired into an adjustable Temp Probe my S/C air box blocks the middle of the radiator decreasing air flow. I used a 16 pusher up front it does keep up except while in traffic with the air on, remember I live in Florida. You will need to play with the Temp adjustment so not to have the fans run too long after the car is stopped.

Landseer

Are any of you seeing the dash temp needle running up and down between the two white lines? (that is, from about the 8 o'clock position, thru horizontal, on towards 10 o'clock?)

My 85 car is doing it. New lower rad sensor, new air pipe temp sensor, new temp II. Electric fan is not running. If I cross the terminals of the lower rad sensor or the air pipe sensor, the fan runs. And when it does, it moves a lot of hot air. Drive normally on a 75degree day and the needle stays below horizontal. Push it, with kickdowns and acceleration, or stop at a light, the needle approaches the line at 10. No fans.


Its weird for me. The needle on the other cars stays at the first line, slightly below, slightly above if pushed.
Those fans aren't running either.

But the 85 seems hot and the fan doesn't run. Why this difference?