i was thinkin about goin back to stock airbox and save the comments about stock bein better than cai, i know. but is it possible to have the stock box and like the CAI tubing also? kinda like OSCAI whtever, the cai tubing goes in the side of the stock box?

 

Sure, why not? Just run some tubing

BTW, stock already pulls cold air.

 

right i know, from that dinky little scoop.

 

you'd be surprised how much air is rammed into that scoop. It was made that way for a reason.

 

ive seen where people use the expanding section on their cai

i feel as though my car actuall y slowed with tha cai addition

 

DR-MAX has done this on his. I saw it in person the other day. Sounds like a cool idea.

 

G4... measure that inlet...I bet it has the same cross sectional area as the the rest of the snorkle.

 

OSCAI ...

 

easiest way to get a factory cold-air intake.

 

First of all, having the RAMming effect from an intake setup is not possible. The only way to get this effect is thru forced induction. Now that this is cleared up onto the fun stuff. You can use a 3" PR CAI up-pipe however, you are going to need a silicon reducer to step down from 3" to 2". Two inches is the largest hole you can hack onto the box, trust me! Then retain the factory air scoop but eliminate the elbow and plug up the hole from the scoop to the elbow. This will concentrate the direction in which the air is being drawn into directly into the airbox, thru the air filter filament, then thru the TB, and finally into the intake manifold. The only concern I have with using the CAI pipe is that its made out of metal. No matter what anyone says, metal conducts heat. Thus it can heat up the air being drawn inside thus reducing the effect of the CAI. Therefore, I ended up using a 2" heater hose (the largest I can find) from Autozone. The one I got is made out of cardboard layered with some type of plastic or vinyle ribbings for flexibility. It has an insulating effect which keeps the air, being drawn-in, cool. I had cut-out a 2" hole into the metal panel next to the battery for cool air source.

Here are some photos: http://www.cardomain.com/ride/382487/2 . I love this setup and would never ever go for any aftermarket intake hypes.

 

All that for a whole 5hp ... At least it was free.. Just like the 5th gen GAB.

 

and now for the real question... notice any hp gains besides the one in the back of your mind??

 

DR_max..I knew you would chime in..
How are the tests coming? I've done a couple myself...

I found that at 30mph there is about 2.5 inches of vaccum at WOT
At 60mph only 1 to 1.5 inches at WOT.
I wouldn't call it "ram air", but it seems to be of help to use the factory snorkel.

 

There is no gain.......except for the balance in high and low tq which were lost whenever you mess with the stock intake setup. You either gain the low end and loose the high end or vice-versa. This is why I reverted back to stock with a little bit of help from a cool air tube. Not only did I get back what I lost but it also improved throttle response for everyday driving. Yes 5 hp is very minimal and is hardly considered a substantial gain no matter what anyone says.

MaxxAddict you obviously didn't read and comprehend the posts I have made regarding this set-up. My intention is not to gain 5hp but to restore the balance in the power bandwith which was lost when you go with either HAI or CAI, worse with the Injen setup (I can already feel the Injen defenders coming this way to rebuttle this). Spending over $100 for that kind of gain is a waste. If you are a track competitor, then you know already not to waste your money on little mods like an intake alone. Do what Ceasar 's Chariot did (NA). If you are a daily driver like me, who likes to get up and go at times, but doesn't live each day with the hopes of breaking track records, then I can say that my setup is better than anyone's HAI. I was able to at least make an educated recommendation based on this. No, I don't have a dyno graph that proves it but why spend $75 on a dyno test that would tell me if I gained or lost 5 hp's anyway? And I do know the difference between the placebo effect that you are referring to and actual performance improvements. You don't hear that aggressive VROOOOM from a stock setup that would trick your mind into thinking that you gained 5 - 15hps.

 

DR-Max, during your various intake modification attempts, which setup have you (or anyone else for that matter) come across that CLOSEST maintains the smooth stock power curve and overall daily driveability, while adding the aggressive "VROOM" sound?

 

well i dunno if he's gonna know totally for sure cause u really can't tell the diff from those setups (except for stock vs. CAI). if u want more air, do what dr did, which is what i would of done if i hadn't hacked the box everywhere. second, the vroom sound will be present if u have a hole in ur box.

 

You can't have both, sorry. If all you care about is the VROOOM sound, go with any aftermarket intake or hack the airbox even. If you care about maintaining the smooth stock power curve, then don't touch the airbox at all. If you wan't to have a slight improvement and allow some more cool air to enter, do what I did.

 

yea i know that. we now know that manipulation of the stock airbox is the way to go. so, what are our options?

1. hacked box
2. OSCAI
3. just remove the snorkel
4. any other ideas?

My question is this: which above setup CLOSEST maintains the smooth stock power curve and overall daily driveability WHILE providing the vroom sound?

 

i know you cant have both. Re-read what i wrote. My question is this: which setup CLOSEST maintains the smooth stock power curve and overall daily driveability WHILE providing the vroom sound?

 

I know exactly what you meant about that question and the answer is STILL none.

The VROOOM sound comes from the air turbulence caused by change in the intake path, ie: cutting a hole into the airbox. If doing so was such a good idea, then why do automobile manufacturers duct these openings with air snorkles instead? The reason is obvious, cooler/denser air means better engine performance. Also, think of the Frankencar mid-pipe versus the stock air resonator. The resonator prevents that harmful air turbulence caused by aftermarket mid-pipe due to its design. Yet many people seems to think that the resonator is bad for performance and restrictive thanks to many manufacturer advertising schemes, they have conditioned people into thinking that a straight-thru pipe would allow more air in. That is why many people buy these intake kits. What these marketing ploys seem to conceil are the bad effects you get from putting a mid-pipe in, they just want to sell people their idea and post some unrealistic dyno graphs of the outcome when you bolt on their product. So back to the airbox, you hack the airbox and you will introduce the same air turbulence only it doesn't really hurt the intake because the air filter acts as a dampener. The VROOOM sound is there but the bad effects isn't. The only side-effect to hacking a whole in the airbox, w/o running some sort of a tube thru it, is the hot air it'll be sucking in. Less dense air hurts engine performance.

Wanna know more??? Read the stickies!

 

I've read the stickies countless times as a matter of fact. Whenever there are no interesting new threads, I re-read the stickies. I think some are outdated/wrong; especially the portion regarding the HP gains from aftermarket intakes.

Automobile manufacturers duct the airbox holes not only for practically (cooler air as you mentioned), but for sound deadening. I'm sure that 99% of maxima buyers don't want to hear the obnoxious roar of their intake. Only young bucks who wanna think they have a muscle car want to hear their intake roar.

 

There is very little in the way of a performance increase that the stock snorkel's RAM effect will have. The reall gain is realized by lowering the intake air temperature, and by not inducing any negative pressure.

Having too many air sources coming in from different locations will lead to decreases in performance because of lost intake vaccum. It may sound really loud and aggressive, but it's bark has very little in the way of bite.

Stick with one primary source of intake air.

 

I have an idea. What about diconnecting the resonator located underneath the battery and somehow patching up that snorkel elbow opening? This way you keep the stock setup, but now w/o the resonator, the intake sound SHOULD be louder, right??

BUT what if the resonator actually provides an additional source of air for the airbox..... hmmm, that would be counter-productive in that case.

 

That idea has been tried and proven. Details are in the stickies......I thought you said you read them.

 

I'm a advocate for the stock intake. Recently removed my HAI and stuck the stock box back in. Not hacked either. Completely stock. The diff is like night and day. Smooth power band. No noise. No low end loss. I did notice a slight drop off of the pull at high end, but the pluses out weigh the one weak spot. The car is more enjoyable to drive now. Automatics and after market intakes don't mix well. It causes too much lag in the response time.

 

I tried this already. I put duct tape securely around the hole of the snorkel and the twisted the tube from the resonator and bit over. The sound it produced was the same as stock. Or at least I didnt notice anything....
I believe the more piping and that curve in the snorkel made it stay quite.

 

meh.

hmmm, I see lots of info about the OSCAI, but not the method I presented.

 

Your description of what you wanted to do is an OSCAI though

 

no. it's not. I wanted to do what goldtooth did. Don't attach a pipe to the snorkel opening. just patch it up in order to eliminate the first resonator under the battery.

 

well, i fully went back to stock today. i patched up some of the holes in the box and kinda did the setup drmax did. i have to say i will miss the sound but i have my exhaust to back it up.

what i did notice was the response was much much better, esp at a stop. puttin the stock box back on cut a few seconds of lag.

 

what would happen if u were to take out the ram air setup completely and run piping from where the snorkel attached down to the front grille?

 

what would happen?... ur car would still be running.

well i don't see that possible. 1st, the inlet is rectangular and second the radiator is behind the grille

 

I love these posts! This was the mod home depot was made for. Just do what DR Max did, but you don't have to cut a hole. You can run the tube behind the battery and headlight and have it come out at the foglight hole, if you don't have a fog light. I fit a 2 1/4 size shop vac hose down there, and I don't think anything bigger will fit. But it keeps the stock smoothness and gives you a little more growl, nothing like a CAI though. And besides CAI and HAI make the engine sound like its working really hard to go not that much faster. And personally I like it when I can hear the other guys engine over mine as I pass him, kinda like I'm not trying... but thats just me.

 

Stock intake is really GOOD.. it's nearly a CAI. It grabs air from the FRONT and air does go in while you drive. But...

Honestly, dont' waste your time and bother hacking and building a CAI stock or whatever. Use the money and time to do something else. Buy a KnN drop in or whatevers...

 

what I am doing is just using the stock resonator with a K&N cone connected to it so i don't lose the use of the resonator. Am i incurring much performance loss (if any) from doing this ? (yeah air will be a bit hotter) but anything else?

 

i think u'll lose velocity in the stock pipe.hence since the resonator is closer it'll draw air mostly from it. other than the front.. honestly don't worry bought it.

 

The gains or losses are too small to really worry about, with any type of intake setup. The whole point of the stock air box is for drivabilty and responce. Any other type of intake is mostly for sound and looks. If you gain in one spot of the power band from a after market intake, you'll lose it somewhere else. Once again, the gains and losses will be very small.

 

I bought an entire, used stock air box off of eBay so that I can do some experiments with it. I have a very sensitive device called a hot wire anemometer that measures air velocity and temperature. In actuality, the mass air flow (MAF) sensor IS like a hot wire anemometer in that it contains a heated wire that is cooled by incoming air - the faster the air flow, the more the wire cools off.

These changes in air velocity are measured by the MAF as voltage changes. Coupled with the intake air temperature sensor, the ECU uses this information to calculate air density and then to adjust the fuel injector pulse accordingly.

To put it simply, cooler air is what leads to power increases since the cooler the air, the denser it is, the more oxygen it contains, and the greater the combustion. The reason CAI's work is because they lower intake air temperature.

The only other way to increase air density is by cramming a lot of air into the throttle body; aka, a true RAM intake.

Conversely, anything you do that results in an increase in air temperature -- such as opening holes in the stock air system that allows hot air from the engine compartment to enter -- will lower density and lower your performance.

The Rule of Thumb in determining air density effects on performance is that for every 10% decrease in intake air temperature, there will be, on average, a 1% increase in horsepower (and vice-versa).

Actually, since heat is the enemy of most systems in your car, such as transmission temperature, oil temperature, coolant temperature, and even brake temperature, anything you can do to reduce heat build-up will give you better performance and increase the life of your car. Remember, that 87% of the energy that gasoline can produce in your car is lost as heat energy -- mostly via friction.

But, I digress. Back to my planned experiments:

I am going to mount the anemometer sensor (that is as small as a matchhead) directly in front of the MAF and calculate air density readings (from velocity and temperature) for various configurations (mods) and at different speeds.

I think this will answer the question as to what really happens when one messes around with a stock intake.

Stay tuned.

 

^^^wow, thats pretty hard core. i also thought maybe wrapping the CAI tubing in exhaust wrap cause as u know, metal conducts heat. but anyways, have fun w/ the experiment

 

Yeppeeeeeeeeee! Another science project. You should switch careers as you seem to be more passionate about this kind of stuff.