How Should I Build My Cold Air Intake?
 

I've got a few ideas on how I should do this, but I'm not sure which is the best. Thing is I can't really move the air filter anywhere else, or at least, not easily. So for now, I'm considering building a shield or two to keep heat away from the intake. I did some 1/2 ass drawings in MS paint that kinda show what I'm thinking of doing.

Some things I'm considering:

Getting cold air to the air filter
Keeping heat away from the air filter
Keeping air moving through the engine bay like normal.

Here's a few sketches I drew up of different. Ideas. These lines would basically be a wall of sheet metal that seals against the car and against the hood when shut.

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Pic 5
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And here's a blank pic if you want to draw your own:

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I'm thinking something like 5 would be the best, but it would also be the hardest to build. I've got sheet metal, shears, and a rivet gun. Figured I'd get some opinions on what to do before I build anything. I'm also thinking of wrapping the hotside pipe with something to help keep heat out of my cold air intake.

5 would be the best IMHO.

you don't have enough room to run pipe down to the left of the intercooler?

No, can't do much of anything as far as relocating the air filter. It may be possible, but not right now. For now, I just want to build some shields to improve my current setup. NB's have a good source of cold air behind the factory drivers headlight. Most after market NB setups put the filter over there, but I have a hotside IC pipe running across that area which is right where the air filter/pipe needs to be. So I'm thinking just build a big box in that corner that encompasses my air filter and just insulate the hotside charge pipe.

I was reading a while back something from Corky Bell; I think, about wrapping the intercooler pipes. Maybe on m.net. Said that they actualy found it to keep intake temps higher because the charge pipes them selves also acted to cool the charge.

don't know how true that is, but just thought I'd share the info.

If the pipe is hotter than the area around it, don't shield it. If it's hotter outside the pipe in that area, do.

Yeah, that was Bell. But in my case, I'm trying to keep heat out of the intake. So wrapping it would likely prove beneficial.

oh , I'm pickin up what you're puttin' down now.

Have you thought about using some fiberglass to mold a floor for your heat shields? you could insulate that and then keep the benefit of leaving your charge pipe in the open, while also shielding your intake from the heat.

Well, no, I haven't thought about that. However, that would probably be outside of what I could do right now. I have everything to do fiberglass work... 270 miles from here. I'm at college now. Aside from that, I don't think it will matter if that extra heat goes to the IC vs. being dumped in the engine bay. That 20* might make for a 1* difference coming out of the IC. That's something, but not much.

However, if I do wrap the pipe, it will probably be with a bunch of fiberglass cloth. :cool:

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So yeah, got a model made of cardboard. It's not finished yet though. Still need to trim the top to be flush with the hood more or less. Any ideas on how to do this? I'm thinking about cutting it too short, then stapling a piece of cardboard on the top on both ends, then sticking a pencil in it. Do this say ever 2 inches, then shut the hood. Open, and all the pencils will have been pushed down to the correct height. From there, it's easy enough to connect the dots. Or is there an easier way?

EDIT: Or I could just build a roof over it. But I'd still want to make it "close" as to not make the box smaller than possible. So open or closed on the top?

which side is the front?

looks good otherwise, I say leaving the top open won't matter. Since you don't have anywhere for the air to be pulled out (extraction hood) and behind the headlight is a high pressure area (i think I recall reading) the air from the radiator and whatnot will just get pushed out the transmission tunnel instead of vaulting your heat shield

5 FTMFW!!!

so far so good.

That looks full of win to me, although I wouldn't wrap the hotside pipes.

Since this side is pressurized, it's going to be at a greater temp or course, and shed a greater amount of heat in your boxed off area. This heat has to be shed one way or another, and the small amount that will go into the "cold" air intake should be greatly overshadowed by the delta T you're getting for the charge side.

Leave it open on top and use some foam insulation of some sort to seal it to the hood when shut.

Yeah, I'm leaning to leaving it open on top and using some foam to seal it up. But the thought of putting a roof over crossed my mind. Might make it quieter. :)

I put front on that piece 3 times in case I cut one of them off... But I did laugh my ass off when I read that post.

To wrap the hotside or not to wrap the hotside is an interesting question. I have two possible scenarios.

A- No wrap, Maybe 5-10 degree warmer temps going into the compressor, maybe 1* cooler temps exiting the IC.
B- Wrap, ambient temp air goes into compressor, ~1*F hotter air goes into engine. I would 'think' that cooler air in the engine is what matters, but I dunno. Perhaps a 5-10*F increase in pre-comp temps moves the efficiency enough to justify wrapping it? I dunno.

What if you got the best of both worlds and put a divider between the filter and the charge pipe?

Nah, that's too complicated. I'll probably just wrap that hot pipe and finish the box. I'll also note I have to build a small "floor" near the air filter as there isn't any car there for my box to touch to seal.

In all honestly, I'm not building the box to make any more power. It's got too much power as it is. I'm doing this to keep the heat away so I can bury that noisy ass filter in foam to make my car quieter. I'm betting putting a roof over it will make it quieter, so I ma do it. But, I dunno, we'll see. If I do that, it will have to attach somehow to the box and be removable without removing the sides, as they will be bolted down from the inside of the box.

just make a piece of plate that contours to the shield from above, weld some nuts and drill some holes into the shield, then use some L-brackets to attach the plate piece to the shield. Perhaps 4 would be enough and all you would have to do is remove 4 bolts to get to your intake. If you got fancy I suppose you could roll or bead the tip of the lid somehow for strength and then add a gasket of some sort (like the type that goes between the cowl area and the hood) to make it more air tight and keep more sound out

bonus: and your hotside ic pipe is shielded

I have something quite similar in my NB (but dont have the pipe running there)

Have a look here:
http://www.cardomain.com/ride/238335/8

http://memimage.cardomain.com/ride_i...0045_large.jpg

For the right height you could just use a flat bar (don't know how to describe better in english) with the lenght of the width of your hood and use that as a level between the left and right fender. Maybe the lower part of the fender at the engine bay... (understandable?)

Greets