Ketchmi

Hey Shane!

I used to run a 2500cfm Perma-cool in the factory shroud and it just didn't cut it down here during the summer in traffic. It does get a bit warm here, wish it would soon!

Shhhh about the driving light idea, someone may try to do it cheaper. (LOL)

Actually mine work great but it just may not be economically feasible. With the labor and parts I need to manufacture, the cost may be too much for reasonable resale. But hey! I can spot deer at about a mile!

I will weigh our fan system as soon as I can locate our scale.

Marc, we have a Lear Jet pilot working here part time that's been giving me pointers but I'm still qualifying on the ground. Have you heard about the new road course going in out here? 4.2 miles with elevation changes! WOOOOOHOOOOO! 370 acre's with two seperate 2 mile tracks that can be combined. Supposed to be "World Class" by all standards and open this fall.

Dave
Motorsport

touque

for us pre-S4 types, what volume of air (cfm) does the stock, pulley-driven fan suck through the radiator?

Fastest928

Hard to tell, to many variables including clutch condition ...but can tell you that it was not enough to cool a stroker. this setup works fine.

CT928

This thread's come along at the perfect time.
My car has the belt adjuster for the fan rather than the air pump. And this has just failed.

I want to upgrade to electric fans because the belt driven fan can't cut it here in summer when the temperature is 50deg C plus.

Does anyone have any pictures of their electric fan mods installed. (Other than the Devek one)

SharkSkin

More pics and details here

PorKen

I hadn't seen that before, nice job + writeup, Dave.

drnick

this plugs into the stock harness and is switched by the signal used to drive the accessory fan on the front, which is removed. they are two kenlowe (UK) 13" and rated at 1380 cfm and about 25A each. they do make a hell of a racket when they switch in!

CT928

How did you secure the Kenlowes to the radiator?
Are normal bosch relays apable of handling the current needed by the fans?

drnick

they come with brackets that arent 928 specific but can be adapted without too much trouble. they have there own relays and thermostatic control included, but the wiring is not that complex. these are the same relay (i think) as is used for the fuel pump.

WallyP

Extensive testing by a major auto manufacturer showed that fans are much more efficient when the blades are mostly outside (behind) the shroud - i.e., the fans work better as a combination of axial and centrifugal flow.

SharkSkin

Thanks!

sublimate

I've seen this said before (perhaps by you) but I'm not quie sure what it means. Does it mean that the ends of the blades are covered by the shroud so that the only air they see comes outword (radially) from the center of the fan? Do you have any pictures or drawings?

Also it seems there is a bit of a tradeoff. Covering some of the fan with the shroud may make the fan work better, but it would decrease the natural air flow when you're driving. As such you fan would have to run at higher road speeds than with a smaller shroud.

CT928

Sharkskin,
I read through your page on the fan installation(impressive) but you don't say if you removed the viscous fan or not?

Bill Ball

By centrifugal do you mean the fan is throwing air to the sides as well as pulling it through (axial), and being inside a shroud restricts that? Oh, so Dave A. might want to try mounting the fan on the rear of his aluminum ring, if there is clearance. Ah. oops! I see Dave A's is a pusher. That changes things, doesn't it?

Oh, and I see Devek appears to have taken this into consideration when mounting the fans in the new setup.

Mark

Just my $.02...
THe new Devek fan kit looks SUPER nice.

Nonetheless, some time ago - I removed the belt driven and front factory electric fans completely and installed a pair of (I think 16") Hayden fans in a push-pull configuration. In normal driving, it RARELY goes above the 1st indicator mark, and even during Florida summer heat DE's and AX's does it get to the 2nd mark. IIRC - total cost was around $150 and 30 minutes of my time. Doesn't look NEAR as nice as Marc & Co's new product - but gets the job done well!