Homemade ram-airs

Is it worth it and how much would it really give me in a 138 hp/148 fpt car????:confused:

Yes, they ARE worth it, if designed correctly. I'd suggest either finding a guide on how to build and design one, or just mimic a quality intake design (I'd suggest looking at an AEM unit and using a design similar to theirs). Go with the largest K&N air filter you can get your hands on and fit under your hood, and use tubing to correctly fit the connector of the filter.

As for gains.. I'd say that you could see as much as 10 horsepower, and 6 to 8 foot-pounds of torque. This is an ideal situation, and you need to design and build your intake correctly to see these kinds of gains. And remember that the biggest benefit of ram-air and cold-air intakes is the increased throttle response. The biggest drawback is that unless you have a poorly designed factory airbox, you will see increased intake temps during idling. The plastics and tubing used in factory intakes are designed not to provide maximum airflow, but usually to supress noise and to allow the car to idle and sit in traffic with minimal rise in intake tempertures. Ram-airs throw the cautions of these design parameters to the wind in favor of power and reponse increases.

Do I run it under the car and up?
Do I run it through the cornering light on the same side as the airbox?
Or do I run it through a scoop in the hood?

I would think that the closer to the intake, the better. Right?

By the way, my car is a 1990 Nissan Stanza.

Going from bigger tubing to smaller tubing(to fit it on the intake) is better right?

If I eliminate the factory air box and simply run it into the car, into the k&n, into another pipe and into the intake, is it fine?

:( So many questions!!!!:(

run the inlet from a point of high pressure on the front end. Ideally this would be in a leading edge near the upper portions of the car, but that's not always possible. I have seen some people who have used a large subwoofer box port (with the radiused edges) and cut out a small section of front bumper to route the incoming air from, the instalation actually looks nice and is probably quite effective. Make sure whatever you design has a trap for water and other debri; that is to say make sure you design the filter into an air box with a low floor and high filter placement. Sealing this whole thing is crucial to maintaining the pressure at speed, so you will need to use some gasketing around the air box opening.

I aslo agree with JD about the power possiblities, just remember that ram air is not effective at lower speeds. Just try to make sure you create a port at least as large as the throttle body (preferrably larger), mount it with special care given to sealing the air pressure in once it's scooped up, and directing this toward the motor's throttle without allowing everything the scoop sucks in to go along with it.

;)

Actually, ram air boosts power all the time. RAM AIR doesn't start to work until about 90 mph. It is the COLD AIR that helps most of the time. High pressure areas are usually around the bumber, as far forward as possible, as the air hasn't started to 'tumble' yet. Old muscle cars (I can't reember which one) used this, and mader more power than the (cooler looking) hood scoops.
:)

Heah dillweed, when did you get the stanza?
IS it maroon in colour?
My mom owned a 90 stanza, but traded it in on her nearly-new grand am (saved 9 canadian grand, or 50 bucks american)
It also had a gray cloth interior.
We got rid of it more than a year age. And it feels faster than it is.:rolleyes:

Thanks Chris,

It's not Maroon, it's Red.

But I was looking at a Maroon one at one time.
It was standard and had 86000 kms on it.

You get about 1 psi of boost at 60 MPH. and the ram air, Trans Ams use it, Some Max Wedge Chryslers, and some Boss Mustangs used it.

I have one on my car, Behind the corner light there is a scoop for the stock intake, I just got a K&N Filter to put in the stock airbox and moved the bulbs and run them without a lens, works good.

Lots of 60's muscle cars used it. I don't know why it isn't more popular. Maybe it can mess up aerodynamics, or maybe good cars use it and just don't flaunt it?
Can someone shed some light on this?

I would say it isn't used as much because of creature confort. To annoying for people that live in changing climates. You don't want to ram your air when it's snowing, when you're following someone down a dirt road, when it's below freezing, etc.

It's just alot easier the the car-makers to put ten more hp into the engine and not worry about all the hassel of making room for ram-air.

Anybody else to help figure this out?:)

Yeah, that makes sense. But in the old muscle cars there is a ring of some stuff, like padding, that help to filter out the dirt, snow, water, etc. And rally cars use ram air, and they drive through dust,mud,water, etc. So I am still a little confused.:confused:

Actually not, the Impreza WRC only uses the ram air on tarmac and hard dirt( where there is not too much dirt)
:confused: A mystery I guess;)

I didn't know that, nic ebit of info.
Also, the WRX uses a ram-air device, so does the Evo (I think), so maybe it just requires more maintanience(spelled that wrong), like replacing that foam and air filter more often.
Still, I'm confused:confused:

I think I found it:

It is useless for the general public 'cause it only makes a worth while difference at around 85-90 mph.

You can't just spend your time speeding, it catches up with you.;)

I see your point, but ram air boosts power throughout speeds, by the cold air. So it is still
confusing. I will e-mail some of the companies and ask why. Sometime.:rolleyes:

Yeah, that's true, cold air induction.

I think bottom line is that the manufacturers just rather a more powerful engine instead.

Heck, why should we be complaining!!
It gives us something to do when we want a few more hp.;)

Amen:cool:

From what I understand, Ram air has little to no value on automobiles.

It has been used to the most benefit in motorcycle production.

For any benefit, it must be used in a place of high air pressure, such as at the base of the windshield where it meets the hood.

Cold air induction is not the same as ram air.

Ram air is basically force feeding your engine as the name implies (RAM the AIR into the engine . . . (?)) . . .

If cold air is what you want you just be sure to route your intake tubing as far away from the heat under the hood as possible, such as intakes that bring in air from behind a fog light or from under the chin spoiler, in front of the wheel well, et cetera.

Those are the same things! the air would go in, and be forced in. Normal induction is under teh hood, with little airflow. Any intake from outside brings in cold air at all speeds, and fast (RAM) air at high (90mph+) speeds. The cold air makes the most difference in real life, as it boosts power no matter the speed, and it boosts it by a lot.

Oh yah, Ram air would have huge advantages for automobiles, and the dis-advantages we have already discussed.

Amen.

so in other words just do it.

Pretty much, yes. I will be emailing companies today!

Originally posted by Chris
I didn't know that, nic ebit of info.
Also, the WRX uses a ram-air device, so does the Evo (I think), so maybe it just requires more maintanience(spelled that wrong), like replacing that foam and air filter more often.
Still, I'm confused:confused:

WRC cars only use ram air for cooling the drivers heads.
Ram on a Turbo charged motor isnt going to give you much in the way of extra hp. Its easier to just wind up the boost another Lb.
They also have restrictor plates on the throttle body, which limit the HP, again adding ram air would net them nothing.
All the vents you see on the bonnets are for engine cooling marketing, and nothing else. Infact the large scoop on the bonnet of the WRC Imprezza is actualy blocked off (the FIA limits the number of open vents), and is only there to help ppl identify the car with the road going WRX, which houses the intercooler under scoop.

hey kurt, to solve this on going dilema let's install one on the old stanza, that will let us know if it is in fact worth doing, and if it is we can install them on our stanzas

Not worth it though.

You can put other mods and get easier horsepower.

Vis: Here, call me Dillweed.

It is essentially free power... it just takes work.
And, yes with turbo's and intercooled, it matters less. But you would have more boost to begine with, and that means less rpm's for the turbo, and it hopefully wont break. I have emailed the manufactures, but none have really answered yet. Also, the air would be cooler going to the intercooler, so it would leavew slightly cooler.
But isnt it fun watching them drive around wearing almost nothing in the cars, sweat pouring down them??

First of all, you don't put ram air when you have a turbo, 'cause the very little boost a ram air gives is dumb in comparison with a turbo. And how could you rig that up anyway. A ram air only starts being usefull on a NA car at around 90 mph.

When you see traps in hoods of turboed cars, its ONLY for the intercooler.

Chris: What do you mean by that last sentence?

This may be a silly, unrelated point, but I thought I would throw this into the mix anyway.

As much as I like the import scene and working with four cylinders, I just about never find them to be as audibly stirring as, say, a Ford Mustang V8. But an intake (home-made or not) can help beef up the sound of your four cylinder.

I was driving yesterday next to a 1999-2000 Honda Civic Si. I noticed that every time the drivier hit the gas, the car emitted some very "muscular" sounds. I drifted behind him to take a look at his exhaust, and to my surprise, it was the stock piece. In fact, I couldn't pick out one detail by looking that did not look completely stock. And I know that Si's do not sound like this right off the dealership lot.

So I pulled up next to the car at a red light, and asked the driver if it was in fact stock. He said it was, except for an intake. Getting your car to sound meaner (and I mean a lot meaner) is in and of itself worth the investment of getting an aftermarket intake, or making your own.

Yeah, he probably had a high-flow air filter, like a K&N or something. That sounds neat.

By my last sentence, I mean it is funt o watch rally drivers in there cars when is 40+degrees out, sweating away years of their life. Theres a german word for it, meaning getting pleasure from someone eleses misfortune.
Anyway, the cold air is the most important. So in a turbo car, you want the air coming in from the fenders (so its cooler, and some extra boost. This means the turbo will be pushed by incoming air, so to achieve the same boost, the turbo can be slightly smaller, and will spool up slightly quicker). A hood intake is good for an intercooler.


PS. Some companies havnt answered yet, so they probably never will. the others just didnt tell me anything.

does anyone know to make an easy homemade intake for a 91 escort 1.9l?

Ram air does only work at high speed, for example I have seen numbers on 0,02 bar pressure increase at 250 km/h or so, this is equal with a 2% power increase.

The intakes will also need to be so large that they affect the drag of the car.

Most people or even companies that make "aftermarket ram air intakes" also use the wrong type of nozzle, the converging type like a subwoofer box port.
The correct nozzle are however the diverging nozzle, that becomes larger after the intake. Or maybe more correct, a type of converging-diverging nozzle, where the diverging type is the "main" nozzle, just like the intake of an aeroengine.

Because of we want a pressure increase (static pressure) we must create a pressure increase of the kinetic energy in the moving air, and this is only possible with a diverging nozzle and in high speeds only.