Cold air intake construction

[Doubt_Incarnate]

So when my motor goes in, i want it to suck the coldest air it can.

Thear are a few ?'s i have that need to be adressed.

First: "X" amount of air is required, So i need a tubing in diameter at least the size of the TB, but how big is too big? Will usig the smallest (matching the TB) produce a sort of limited ram effect since "X" air has to fit through the smaller tube? or is that just wishfull thinking? is there really any benifit to making a 3" intake?

next: Aluminum is like the best heat condutor around, so why should i use it for this? i cant use fiberglass can i? isnt there some thermal safe plastic i can use? that way i dont have to wrap the aluminum to sheild it from absorbing heat.

last: it doesnt really apply to the CAI, but i need to throw it out there. In order to convince my ecm to retard the timing so my motor doesnt detonate, iwas going to relocate my IAT sensor to where the egr valve would be, it would sense warmer air and not advance the timing accordingly (but would it not add the right amount of fuel?), using a phenolic material to mount it so it doesnt soak up a ton of heat from the aluminum. is that a workable idea or should i try something else?

[geoffinbc]

You can use PVC or ABS pipe. But it is ugly.

Your motor has a knock sensor. It will retard timing for you. If your compresion is high then you need to run high octane gas. Start at the highest and then bring it down until it pings. Once there go back to the next level up.

[Doubt_Incarnate]

ok, sounds good, i was just looking for a little added security, not so nervous as i have searched around and found some guy says he has 13:1, and who am i to say he hasn't?

so if pvc and abs is ok, could i just use fiberglass and form tubes with it? i can smooth that up and paint it to match things Its not so heat conductive, and is probably just as light, if not lighter, than aluminum. i figured it would sine the hood is fiberglass, and so are most boats, even inboards.

[geoffinbc]

Yes you could use fiberglass. I would form it over a pipe coated in a release agent or a grease the you could pull the pipe out after you finished the fiber glass really nice.

[vsop4me3.1]

I used 3" pipe. the first intake I made was plastic, and later moved to aluminum. If you go with fiberglass make sure to post pics and let us know how much it cost. i spend about $17 on the plastic one and about $60 w/shipping on the aluminum.

[Doubt_Incarnate]

i had the same idea with the tube, great minds think alike...

i know fiberglass stuff isnt the cheapest, but it wont be anywhere close to the $195 mantapart wants. if all goes well my car should be home next month and i can swap the the motors and get it running, then i'll have it on hand to make the CAI.

[RednBlack]

You can use PVC or ABS pipe. But it is ugly.

Not ugly if you can't see it. Mine comes out of the bottom of the stock box, and sucks air from the air dam, 6" off the ground. And it is painted black, so it is virtually invisible. You have to look hard to see it. Actually it doesn't suck, it is rammed in.

[Doubt_Incarnate]

as long as it works!

[RednBlack]

In my opinion, this is the cheapest and most positive mod you can do to a vehicle. Seat of the pants performance is well worth 20 bucks and a couple hours labor.

[Doubt_Incarnate]

seat of the pants, the butt dyno. thats really all im looking for in the end, does my car feel fast? even if it flopped out 18 sec 1/4, if it felt like it was 12 in the 1/4, i wouldnt really care.

[StudlyCamaro]

i used 3" PVC on my first CAI, and it felt just as strong as the K&N i replaced it with

[RednBlack]

Just for the record, K&N is overated. The only advantage of a K&N filter is that they are reusable. Stock filters flow just as well. That is not just my opinion. But in my opinion, putting a cone filter under the hood, sux...Hot air. Everyone agrees that cold air is best. I see no point in underhood air. It is moronic.

[Doubt_Incarnate]

I'd get the k&n because they seem to be everywhere, readily available.

looks ike 3" is the standerd so i' guess i'll go with that, i just need to draw up some stuff so i can make good curves, cant really slip a tube off of another if bent 45 can you? or i could cut it down one side and pop it off and strap it back shut, that looks like the easiet option.

[94CuttySL]

My first intake I bought for my (last) car was powedercoated steel, not AS good as aluminum, but it was custom and very nice. I used a K&N X-Stream (RX-4750) filter.



Since money was a factor, I did manage to make an intake for a friend out of 3" PVC conduit, I painted it white, and put a generic cheapy cone filter on, here are some pics. PVC isn't ugly if you dress it up a little:







One of the downsides to the one I made is the rubber reducers. Silicone is best because of it's ability to flex.