Cold air intake for $11

Scottwax · 12-09-07, 09:09

I did a similar cold air intake on my Accord and was pleased to see I could make one for my Maxima. The main problem for me with aftermarket CAI's is the increased intake noise. I know some people like it but I want to keep my car as quiet as possible.

Anyway, I did some searching on maxima.org and found out the easiest way was to keep the factory intake scoop at the front of the car and run a tube from the bottom of the ducting to under the front fender. There is a 3.5" diameter capped tube near where the intake ducting goes into the air box. Not sure what the exact purpose is, may be a resonator of some sort. I simply cut the closed end off and attached 4" dryer ducting to it using a 4" worm clamp-total cost, $11. I then used a box cutter to cut out a hole in the splash guard so the hose is drawing air from outside the engine bay. The hose ending is about 6" off the ground but I shouldn't have any problems with pulling water into the engine should I go through a deep puddle since the factory intake scoop is still in place. Should water get into the tube, the engine would pull air through the stock intake instead, sort of like when a straw has a crack in it.

Here are a few pictures. Yeah, the front lip is pretty scuffed up but I can't see it unless I get down there so no biggie.

The engine seems to pull a bit harder from 3500 rpm and up, most noticable from 5000 to the 6500 rpm redline. Maxima.org members say it typically shows a 5 hp increase on a dyno. Not bad for $11, eh?

DieselMDX · 12-09-07, 09:11

great idea

Way2SSlow · 12-09-07, 06:59

Watch for puddles....I know it's unlikely, but I used to have a Ram Air system underneath my bumper for the pala and I was always worried it'd take in some water.

$11 for any kind of performance benefit is AWESOME!

Monte78Carlo2k1 · 12-09-07, 07:23

Where is the filter element?

Scottwax · 12-09-07, 08:33

Quote:

Originally Posted by Monte78Carlo2k1

Where is the filter element?

It is in the stock air box that is behind the battery. Still as quiet as stock.

Monte78Carlo2k1 · 12-09-07, 08:54

Ah I see that now. Very interesting set up. Can't beat the price either.

74 thing · 12-09-07, 08:54

Once a horsepower guy, always a horsepower guy! Nice mod Scott and by keeping the stock intake box it will keep the intake noise down. When you remove the box-it gets louder!

Setec Astronomy · 12-09-07, 08:58

Quote:

Originally Posted by Way2SSlow

Watch for puddles....I know it's unlikely, but I used to have a Ram Air system underneath my bumper for the pala and I was always worried it'd take in some water.

Ditto...my stock intake on my '90 Bonneville used to inhale water when you were on the highway and had to stay in lane and drive through standing water at the edge of the lane--the kind that slows you down...would throw water up and the engine would glug glug. It was bad enough you'd worry about planing off the road...then you'd have to worry about the car dying and getting rear-ended. I don't think it ever stalled though...would just run like crap for a few minutes after.

todd@bsaw · 12-09-07, 09:14

I know lots of guys that have "swiss-cheesed" their stock air box. Take a 1/2" drill bit and just fill the air box with holes. Pulls more air into the intake and you do not have to worry about the possibility of hydrolock.

dazzerjp · 12-09-07, 10:25

nice motor.

i would be too worried about having an exposed intake that low down.

cant you put a filter or fine mesh over the hole?

my friend did similar on his type r and had lots of problems with dead insects and leaves clogging up his air filter.

the swiss cheese style airbox is questionable as unless your airbox is a good way away from the engine, the box will just be pulling in hot air.

SpoiledMan · 12-09-07, 10:47

Nice Scott. Mine is a about 4-5" off the ground and it hasn't taken in any water. Oh wait, I don't drive my car in the rain.

Scottwax · 12-09-07, 10:57

Quote:

Originally Posted by todd@bsaw

I know lots of guys that have "swiss-cheesed" their stock air box. Take a 1/2" drill bit and just fill the air box with holes. Pulls more air into the intake and you do not have to worry about the possibility of hydrolock.

Ah yes, the GAB (ghetto air box) mod. One of the guys posted a way to use a hangr that allows you to remove the filter holder (slides right into the air box) while still holding the filter in place. Many of them use it conjunction with the cold air intake mod. I'll probably end up using some sort of mesh to keep crap out of the air box.

No worries with hydrolock anyway since the stock intake tract is intact. Like I said in the first post, it will act like a hole in a straw. Sort of like the bypass valve that AEM makes for their cold air intakes.

When I did this to my Accord, I replaced the factory resonator in the fender with two 2" hoses that run to the bottom of the splash guard and never had a problem in the rain...and that was a set up that had only those two tubes as a way for air to get into the engine-definitely a danger of hydrolock but if I couldn't see the curb, I didn't go down that street.

Anyway, just trying to up the performance without making the car loud. Maybe do headers and the y-pipe but leave the rest of the exhaust stock. Probably do the phenolic intake manifold spacers when I change the plugs since the intake has to come off anyway to access the plugs on the rear bank. Headers, cat back and a cold air intake already has one 5.5 gen ('02/03 Maxima) in the high 13s @ 99 mph with an automatic.

Oh yeah, Transgo makes a shift kit for my car. Nice having something that gets aftermarket support after driving a 626 for 3 years.