DIY - Air Box Mod

[midnightmadman]

Originally Posted by twalker294

I have just put up a very short (12 seconds,) video of my truck with the airbox mod. Other than that my truck is completely stock (until tomorrow that is ;-)

I have all the windows up during this clip. Pardon my son talking from the back seat at the end :-)

I'll likely post another vid tomorrow after getting my Flowmaster 50 series and stainless exhaust tip...

Todd

I love the sound! Mine sounds raspy too!

[SirStrider]

great posts, Titan4x4Aggie and the rest of you - just wish I had read far enough to get to the hot knife before I did it.

I figured this deserved a bump^^^

The other day it finally got above freezing, so I decided to do this and a couple of others that were on hold. I used a jigsaw with a hacksaw type blade and cut it in place -- tons of dust to clean up. Go with the hot knife. But, I am going back with the hot knife and clean up the cut.

SO, I cut the snorkle, dropped in my K&N high-flow panel for the first time, and added my ECO-3 (hate to mention that here, but I did).

Couldn't wait to retrain the ECU, so took it out immediately. again, WOW - sounds better at all rpms'. Now, I don't go to the dragstrip, and don't have a dyno, so all I have is the SOTP dyno. And, since this is what my brain listens to, if it is happy, my brain is happy.

And, my brain is VERY happy with these mods. Starting from dead stop, or rolling from 35 or 70 mph, it FEELS quicker. The engine SEEMS to rev quicker, and certainly SEEMS to reach 6500 rpm much faster - in gear. And, I'm burning a lot more rubber than I could before.

So, I say, my brain tells me these mods worked GREAT!!!

Next mod - TB bypass with valve... will have to wait -- it is 11 degrees out there with a wind chill of -4... Don't need the bypass at this temp!!!

Next year - pipes...

BTW - I am a electrical engineer, and my 35 year trained engineering mind guesses that bigger/less pipe ==> less impedance (resistance for you mechanical engineers, but I am really talking inductance and capacitance too) ==> faster response to vacuum. It's a common sense thing. Results from models are only as good as the model...

To test this theory, start your vacuum cleaner with no attachment on the wand. Listen to the moter. Now, stick your tongue in the wand. Sounds more restrained, doesn't it. Now, go to the hospital and take your tongue with you...

I hate equations...

My mind is happy. My foot is heavy. My wallet is sad...

[midnightmadman]

Originally Posted by SirStrider

great posts, Titan4x4Aggie and the rest of you - just wish I had read far enough to get to the hot knife before I did it.

I figured this deserved a bump^^^

The other day it finally got above freezing, so I decided to do this and a couple of others that were on hold. I used a jigsaw with a hacksaw type blade and cut it in place -- tons of dust to clean up. Go with the hot knife. But, I am going back with the hot knife and clean up the cut.

SO, I cut the snorkle, dropped in my K&N high-flow panel for the first time, and added my ECO-3 (hate to mention that here, but I did).

Couldn't wait to retrain the ECU, so took it out immediately. again, WOW - sounds better at all rpms'. Now, I don't go to the dragstrip, and don't have a dyno, so all I have is the SOTP dyno. And, since this is what my brain listens to, if it is happy, my brain is happy.

And, my brain is VERY happy with these mods. Starting from dead stop, or rolling from 35 or 70 mph, it FEELS quicker. The engine SEEMS to rev quicker, and certainly SEEMS to reach 6500 rpm much faster - in gear. And, I'm burning a lot more rubber than I could before.

So, I say, my brain tells me these mods worked GREAT!!!

Next mod - TB bypass with valve... will have to wait -- it is 11 degrees out there with a wind chill of -4... Don't need the bypass at this temp!!!

Next year - pipes...

BTW - I am a electrical engineer, and my 35 year trained engineering mind guesses that bigger/less pipe ==> less impedance (resistance for you mechanical engineers, but I am really talking inductance and capacitance too) ==> faster response to vacuum. It's a common sense thing. Results from models are only as good as the model...

To test this theory, start your vacuum cleaner with no attachment on the wand. Listen to the moter. Now, stick your tongue in the wand. Sounds more restrained, doesn't it. Now, go to the hospital and take your tongue with you...

I hate equations...

My mind is happy. My foot is heavy. My wallet is sad...

Did you cut that long tube that goes into the fender also? No need for it to be in that deep.

[SirStrider]

Originally Posted by midnightmadman

Did you cut that long tube that goes into the fender also? No need for it to be in that deep.

Yeah, I saw that in your post. Should be warm enough tomorrow to take a look at it. Someone posted that they removed a screen and it increased flow - don't know exactly what screen that is, but will look.

I was also thinking that there was no reason that thrust_titan's DIY custom air scoop to the grill wouldn't work with the OEM box - have to find that thread. Forgot what he did. I think it was with an AEM or Brute Force CAI. Has to be at least as good at the piddly ram scoop for the Volant.

Now, they are calling for rain. Can't win... I have about 15 projects lined up...

[BigJeesh]

Did it, love it! Sounds great and I notice a small amount of increase in my low end...

["THE KIZE"]

I agree with your thesis but there is still flow to the entire filter with stock snorkel,shortening the snorkel allows evenflow over the whole filter but does not volumize more air and that is what makes more power.I do believe that you could experience a gain and more importantly open the entire filter up to breathing,so inturn contaminated air is not just collecting particulate on that one corner of the filter,which would rob hp at that point.very interesting modification.and worth doing,but why would nissan engineer the snorkel to do this?

[sudden urge]

Originally Posted by THE KIZE

I agree with your thesis but there is still flow to the entire filter with stock snorkel,shortening the snorkel allows evenflow over the whole filter but does not volumize more air and that is what makes more power.I do believe that you could experience a gain and more importantly open the entire filter up to breathing,so inturn contaminated air is not just collecting particulate on that one corner of the filter,which would rob hp at that point.very interesting modification.and worth doing,but why would nissan engineer the snorkel to do this?

Because of noise. The mod creates a Waaaaaaaa sound at heavier throttle, and I'm fairly certain that is why Nissan would not consider it.

[3Riverssouth]

I've read through almost all of the post on this thread and don't see why this is not a good idea unless you don't like the extra noise.

I will be doing this Christmas day if I get the gift I've been asking for.

[RB's Titan]

Originally Posted by sudden urge

The mod creates a Waaaaaaaa sound

Wahaaaaa...LOL More like GRRRRrrrrrrr....sorry just had to. Did it to mine coupled with Fram Air Hog and then recorded the data using Cipher the combo pulled in more air gm/s than stock.

[moore101]

Does the air box mod hurt or help with the whistle/whine noise the stock intake makes? That high-pitched sound is driving me crazy.

[sudden urge]

Originally Posted by moore101

Does the air box mod hurt or help with the whistle/whine noise the stock intake makes? That high-pitched sound is driving me crazy.

There is no whine or whistle noise with the stock airbox before or after the mod, obviously, you have something thats not sealed properly imo.

[xterraintx]

OK, with a TrueFlow CAI (uses stock box) would it be an additional plus factor to do this mod too?

Just checkin

[Wiscdave]

I have a used KN drop-in, good condition. $25 shipped PM me.

[FtWTitan]

From a fluid mechanics perspective, this mod will not increase or decrease your air flow, with the assumption that in both cases your filter is clean. Lengthening or shortening the tube in itself will not change the mass flow rate of the air.

What it will do, obviously, is increase the area of the filter over which the air flows through. The air will still concentrate more over a certain section of the filter, but it will be broader than the stock model. This will at least help maintain that "clean filter" state longer.

The only drawback I could see would be the already mentioned increase in noise from the intake, which is probably minimal, especially if you have an aftermarket exhaust. I'll be heating up the knife myself eventually

[SirStrider]

Originally Posted by Wiscdave

I have a used KN drop-in, good condition. $25 shipped PM me.

Dang - paid almost twice that - but that was before I figured out this site!!!

No whine before or after for me, either.

I never did hear the Waaaaaaaaaaaaaa, either. and now, with the magnaflow muffler, all I hear is the exhaust, and I love it.

Snorkle mod, K&N filter and 12256 Magnaflow is the cheapest way to get close to CAI and full exhaust. under $200 if you shop around. Big, big difference. sounds great and feels great. Oh, and the 2 degree advance. I am exceedingly pleased.

As to why Nissan doesn't do these simple things - I'm sure it is the noise. Definitely a head-turner. Even the guys up at my dealer were impressed when I told them how cheap this could be done. A couple of the techs are now friends, and do my consult work free - couldn't be better.

If you live near Blue Springs, MO, and need the 2 degree advance - PM me and I'll try to get you in free...

Thanks, guys, for all your suggestions. Saved me big money!!!