Contour Enthusiasts Group Archives Forums Modifications Duratec Performance Hood scoop / Ram Air idea

(Old message, I know; found it with search

**hEcH-HEm** Excuse me... anyway...

I'm doing this. My intake plans are as follows:

1. Monster Flow or KKM air filter mated to the SVT fender duct;

2. BAT inlet pipe

3. 75mm MAF

4. Running 3" hose from wheel-well-side fender duct to front bumper opening

5. 12v electric 100 CFM fan mounted at bumper
URL:
12v mini box fan at NorthernTool.com

6. 12v electric 100 CFM (the same) mounted somewhere near fender opening; don't know where, yet.

This might be a pain to make all of this work, but since I KNOW it can be done, I'm giving it a shot.

While fan-shopping, I was REALLY, REALLY hoping to find something in 3.5" or smaller that pushes 200 CFM or more... but couldn't find a thing. This is as close as I got.

Anyone know of a fan meeting or exceeding these specs??

.RMk..

what is the fan supposed to do, other then drain your battery and tax your alternator?

First off, no, I'm not worried about two 12V fans draining the battery. :rolleyes:

At idle, the fans would assist in moving the air from the duct opening in the front bumper to the fender duct, and from there through the filter and to the throttle body... and when the TB is opened, more quickly through the runners.

Nearly 200cfm is better than the estimated 23cfm the intake receives at a stand-still.

The extra airflow from the fans should be able to help propel the vehicle from a stand-still, but I wouldn't expect much once you get to 4000rpm.

From what I've heard (here), greater air speed = greater torque. With two fans pushing air to the TB -- even at idle -- there's bound to be an improvement when you hit the accelerator.

It all depends on whether or not two 100cfm fans is enough to show an obvious improvement. They may be completely unneccesary and could possibly hinder the airflow (though IMO, that's unlikely).

It doesn't seem that two fans would restrict air flow as long as the blades are spinning... but as with anything this weird and nubile, we won't know until I or somebody else tries it.

In sum, it's a kind of mock "electric turbo"; it's different only in that it's MUCH less expensive and... well, a little less professional looking.

Aside from the performance benefit, it's possible (isn't it?) that with the extra air blowing through the engine, the fuel would burn a little 'leaner' and conserve more fuel. Correct me if I'm wrong...

.RMk.. "I'll take on anything that even seems like a good idea."

i guess in theory, it has the basis for a good idea. but i think there is more to it then just cfm. i believe it is the lb/min of air that increases performance. also, when your car runs leaner because of increased air into the engine, you are not using less fuel, you are just adding more air. you would be running more efficiently, but not using less fuel. i just don't see how 2 12v 100cfm fans could do anything for you. i know this is apples to oranges... but i believe those fans spin anywhere from 3000-6000 rpm, where a turbo has to break into 10,000+ rpm just to overcome heat deffiancy and actually start producing more power then it is comsuming...

If I were you, I would not spend a lot of time or money working on that fan setup.

First off, you are correct about the fan moving more cfm than the engine can use. At first look, this seems promising, but because this is a fan and not a pump, it will not be able to produce the pressures required to force the extra air into the engine.

For a real-life analogy:
Consider taking a 5000 cfm box fan and putting it in the doorway of a closet. Then seal up the doorway and turn on the fan. Even though the fan would fill the closet up with air, the fan would not be capable of pressurizing the closet any more than about .05 psi. The fan blades would spin, but the static pressure of the closet would not allow the fan to put any more air into the room.

Now, if you took an air compressor and plugged it into the closet, the pressure would increase, but the volume of air would change only slightly (the walls would expand minutely).

The beauty of a supercharger or a turbocharger is that it combines both an air compressor with a fan. That is why they are so expensive. They must maintain extreme tolerances in order to perform their tasks. A turbo or supercharger with loose tolerances would not be able to create enough pressure to be effective.

On a different note, once the engine reached over 4,000 rpm (figure 23cfm requirement per 1,000 rpm), the fan would only be an obstacle to the flow of the air. You definitely would not want to run with a blockage in your intake path.

If you could find a turbocharger and hook up an electric motor to it, then you may have something, but don't waste your time with a fan.


Dave

This response should cover both bret's and Dave's comments...

First of all, and again, I don't claim to be an expert in the field of automotive performance; I claim to be a complete idiot there... which is my first purpose to being here with my first car... which only happens to be a Contour since I wanted something more responsive than those I've driven.. test drive reviews led me to my Mystique.

I could have gone with the black/tan Mitsubishi 3000GT VR4 I was looking at, but then I wouldn't have this huge support group. (I have to comfort myself somehow. :))

Anyway...



I'm not really looking for a huge HP or torque increase. The idea here is to push cooler (outside) air through the filter, and as I'd assume, two 100cfm fans (or more if I can find better, and I hope I can) blowing through a 3.5" intake pipe is better than trying to scavenge air into the fender from underneath the car through the simple movement of the vehicle.



I don't expect the two 12v, 100cfm fans to force air into the engine.. just assist in moving the air that's already going in.. which they would.. I assume. As for the fans being a blockage, you have to account for the idea of one fan sucking air in from the bumper and another just afront of the filter pushing the air from the first fan (now moving at a greater speed) from there to the TB.

Like I said, it only seems like a good idea now, since it's purely speculation in concept; once it's tried we'll know whether or not it is.

.RMk..

RmK, I'm looking into a similar setup myself.

I'm counting on using three 12V 130 cfm fans. That ought to cover the needs, even at WOT.

Sure, I'm not going to get 1 psig boost with this setup : I'll be lucky to get .25 psig below 4000 rpms. But at the very least, this and a sealed box will make the ultimate cold air setup. Also Bret, the stock airbox and after market setups (KKM) all operate at a slight VACUUM at wot (depending on restriction, KKM should be close to zero psig) So any pressure at all should be welcome.