Another Cold Air Intake Idea

[Mazda_Brian]

Hi guys,

I was thinking of getting a CAI system, but then I dont want holes at the front of the car, I dont want a POD under the car somewhere where it will get dirtier, or be at risk of stone flick-ups and other ****.

I had an idea to build an Intercooled CAI system, but after putting it to practice on a friend's car, the price - gain wasn't worth looking at (about $300 to get an extra 2 - 5HP at speed).

I also wanted to get a couple of bonnect vents to keep things cooler under the bonnet, and this got me thinking.

If I got 2 bonnet vents, and ducted the air intake to mate flush to the bonnet straight under one of the vents, and used rubber seals to make sure it was sealed, I could get the air intake to suck the air straight from the air passing over the bonnet (which is always pretty cool air), the other side would be pretty much there for show, but would still give adequate cooling under the bonnet anyway.

I was looking at the Cosworth Vents on this site http://www.ssv.com.au/cache/item-153....html?cache=no as the contender for my pair of vents, as their sale price is for "pair".

What do you guys think, do you reckon it would work, and if it was only a gain of about 5 horses, it's still worth it because it does look half decent as well.

B.

[Toyboy]

And what about when it rains,did you think about that :wink:

[Mazda_Brian]

My Air intake already has a drainage hole and "valley" for if/when water gets in. If water was to get into the intake, in small amounts it's good, it helps take more heat out of the air, thus cooler air, which is better, but if a lot gets in, it will drain.

I dont think there will be much of a problem, as long as knowbody sits there with a hose filling my CAI up.

B.

[Mizda_Mazda]

I heard NACA profiles are the best for air intake. I'm not sure if they have a website but you should check them out, I think some places sell NACA profile intakes.

About the rain water problem. I read in this mag that you can get a foam segment in intake pipe, they called it a air bypass valve, any way it looks like it justs lets the water exit out the edge of the foam wall.

[Cosmo Dude]

I've thought of using the cosworth vents but having a duct upto the under side of a pod and the vent above to realy promote colder air flow and cool under the hood.
As for water... You can always cool the intake charge with a fine water spray (water injection) but you'd need to find a good way to trigger it so you didn't swamp the engine at idle.

[Mazda_Brian]

You could alway put a sensor on the accelerator, if it was pushed mo than 1/2, it would give a quick 1 second sqirt.

What I am planning on doing with m car is using the existing air box setup (stock setup), and plumbing it to meet flush and sealed to the bonnet, and sticking a Cosworth vent above to draw the air from. Idea is that the vent wll be meshed, and the plumbing also meshed (just before the rubber seals), but the bonnet comes down, and meets firm, but flush and this gives a good breathing duct for cold outside air.

The beauty of the design is that you can have the SHORTEST piping ever for a CAI, making the air travel much less, and thus keeping cold air demand and having less piping to warm the air back up. No changing MAF sensor location, no changing current mounting, etc.

B.

[platypus]

get some bonnet spacers, to let the heat out the back of the engine bay

[Cosmo Dude]

The Cosworth vent is designed as a vent, it disrupts the air in a way that it promotes air flow from inside to outside. Turned around I doubt it woud grab air and force it into the CAI.
The NACA duct, plumbed with a trap and drain would be a better idea IMHO.

[joe_mazda]

World rally cars have a Cold air setup,

Ive seen a Focus with the front vent/scoop (its a funny sort of thing :lol: ) And it had 2 fans like a radiator fan directly underneath it. Im guessing the air enters and spins the fans up (or the fans are already running) and literally cools the engine bay right down and thus improving performance a hell of a lot.

Mind you Ford have a mighty big budget and lots of technical people, not just your average motorist :lol: :lol:

In theory i reckon your plan would work, but its whether it'll work enough to notice :wink:

[geetee]

i reckon it sounds like a bit of an effort for what could be minimal gains.
decent sized ducting to the air filter would be just as effective imo. then you could block off the air filter from the engine bay with sheet material like stainless or ally... :?
i`m sure someone on here put up a pic once of a dutch BA(?) with the intake pipe sticking through the bonnet just before the throttle body. wouldn`t this help with cooling.

[Mazda_Brian]

Originally Posted by Cosmo Dude

The Cosworth vent is designed as a vent, it disrupts the air in a way that it promotes air flow from inside to outside.

I checked the function of the Cosworth vent, and it's for "drawing" air from the engine bay, to promote air entry from under the engine (hot air on top, cold air at the bottom).

I will have to find a different vern to do this job, because the Cosworth will suck the air away from my intake, causing other issues, and turned around, wont do all that much.

Maybe a small-sih scoop would be good, but so-far all the "air scoops" I have found are stick-on crap, even some of the vents I had a look at are stick-on, what performance gain are you going to get by sticking **** onto the car, some of these products merely posses "wank-factor" value and nothing more.

Once I find the right vent/scoop, I will give the idea a go, worst that will happen is I will have a vent on my bonnet, and still be using the original air intake, which I dont see as an overly bad thing. Best that will happen is a new very short piped CAI style system that adds some performance to the car.

B.

[geetee]

can i ask why you don`t want a vent at the front of the car? :? what car you got?

[Mazda_Brian]

My idea was to shorten the intake pipe as much as possible, once you have a long pipe, you lees velocity of the air, and the engine has to work harder to draw the air back, so the shortest possible pipe would go from the air intake to the top of the bonnet, and then you can stick a scoop or vent in to allow the air to get into the intake.

I have a Mazda 626 sports hatch (94 model).

B.

[geetee]

some sort of scoop would be the best option IMO.
but any cold air gain you get might be cancelled out or at least reduced with the loss in aerodynamics.
can`t you fit some decent sized ducting, maybe 4" or even 6", and make a shroud round the filter? sounds to me like you really want a hole in your bonnet. :lol:
if thats the case then maybe just a hole with alloy mesh or something stuck to the underside of the bonnet. still got the water ingress problem though...... :?

[platypus]

yes but when you shorten the piping you also are gonna screw up your idle....

as you have less available air in the piping, your gonna have problems maintaining air coming into the engine

[Mazda_Brian]

The pipe will become about 2 - 5 inches shorter than stock, and will still maintain the pipe that goes from the intake to the ait box and MAF sensors.

it's basically going to go from the air box to the bonnet, instead of the airbox to the little restricted hole at the front just under the bonnet opening.

B.

[sik astina]

What about movin the filter in a cooler spot? thats what i did.

[Mazda_Brian]

thought about that, but then it's a stock CAI system, not a new and inovative idea

Also, running pipe past a certain length will reduce the air velocity, thus lowering the performance factor.

My idea was to stick as close to possible to the normal length (which doesn't reach the cold areas) and draw cold are from a body panel that has air flow over the top.

B.

[platypus]

so your really trying to get a ram air idea?

good luck with creating boost

[ranoverbyamazada]

quick idea look at a 95 ford ef model check out the scoop sits right near the front of bonnet.
just a thought