xbchance

Here's a question, to be answered as if you were trying to explain to a 10 year old:

What is the point/purpose of the Cold Air Intake?

I went back and forth [only because I hear it's only around 2 HP added], and still don't really know what it does or why people like it.

Searched the forum but most all seem to be in the know, so consider your answer as if a quick tutorial.
Thanks! :twisted:
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ncscion

it allows more air to flow into t/b b/c you do away with the restrictive factory airbox. alot of times getting a CAI will relocate the filter and pipe where it can also receive cooler air which in turn helps performance.

CBSIMONSEZ

See if this helps, assuming you have some idea as to what the injection process is about.

STOCK CAR INTAKE. Because of noise restrictions, and various other reasons, the intake ( where outside air ) enters the engine is restrictive and cumbersome. Most new car have a box that is full of baffels, to help keep noise down. This causes turbulence in the Trottle Body and on into the engine. When you step on the pedal, the Throttle Body opens and allows more air into the engine. Works great for stock.

MODIFIED AIR INTAKE. aka Cold Air Intake. By removing the resinator box with the baffles, and smoothing out the inside surface to the throttle body, mean less resistance. If you add in a better air filter, which allows for more air to enter, this also helps. Now, if the C.A.I. is done right, it will route the filter to a place in the engine where it can get the coldest air possible ( the colder the better, cold air fires better in the cylinders ). One side affect is a difference in sound while accelerating, kinda of like a growl. This sound is the air being sucked in with out anything to block its path to the throttle body. One good side affect is better throttle response, esp from a dead stop.

Think of it like this .... remember those crazy bendy straws from like 15 years ago? The ones with all the loops and zig-zags? Remember how long and hard you had to suck ( easy there guys ) to get the soda out of the glass? It was a hell of alot harder the just the plain ol straight as an arrow white with red and blue stripe straw, this one required little effort to get a drink. Same principal, the more direct the route, the better.

scionracerxb

WEll SAID!

Giovanni

Hello there fellas. Just thought I would poke my head in here and elaborate on a couple things.

CBSIMONSEZ was correct when he said "the colder the better, cold air fires better in the cylinders" , but many people don't have the first clue why.

Without getting all techincal, in a nutshell, colder air is more dense than warmer air therefore far more cold air can be pushed into a cylinder than warm. Cold air = more combustion = more power.

This is the principle behind turbos and superchargers. The only advantage to having CAI over turbo or SC's is nothing else has to be modified to use them. Turbo's and SC's usually require some type of custom fabrication and require a higher octane to run, not to mention the drastic difference in $$$$$$.

In short, an engine that breathes better performs better.

G

SCI_FIRE

Best explanations I have read, so far. Thx, guys. :D

rjsalvi

To elaborate on this...most newer cars have various sensors that monitor engine performance. Some of these sensors directly regulate the amount of fuel squirted by the injectors to maintain what's known as a stoichiometric mixture -- the air/fuel ratio. For most normally aspirated cars running on gasoline, that A/F ratio is 14.7:1. At 14.7 parts air to 1 part fuel, in theory the engine should be able to combust 100% of the A/F mixture which by extension, constitutes maximum efficiency.

Without veering too far off the mark, let's say one changes their stock air filter for a cold air intake. By design, the CAI positions the filter element in the flow of cold air. Temperatures inside an engine compartment can reach double the ambient temperature outside. With a stock air filter located inside the engine compartment, the air that's drawn into the engine -- the intake charge -- is less dense than the outside air because air molecules move faster in heat which means that the molecules are *not* tightly packed. In cold air however -- in which the molecules are moving slower -- they're more tightly packed which in turn increases air density.

Getting back to engine management with sensors...if you increase the air density of the intake charge, you're in effect increasing the amount of oxygen entering the engine. If the engine monitoring sensors detect a more oxygen rich environment, they're going to tell the injectors to squirt more fuel. MORE AIR + MORE FUEL = MORE POWER with an internal combustion engine. So it's not just that the air is cold, it's because the engine sensors detect a lean situation and correct it by dumping more fuel in. Now you might ask: "Won't this hurt gas mileage?" Not necessarily...or not unless your foot feels heavy all of a sudden. Why? Generally speaking and only in the context of a CAI, if an engine is creating more HP, it requires less throttle opening to push the vehicle with the same velocity than it did prior to the HP increase. IOW, your engine has the ability to do more work with less effort.

How else can a CAI affect performance? Depending upon design, a CAI can also increase the velocity of the incoming air. Think velocity stack. If you've read any of the comments from users of "short runner" CAI's, most seem to swear that they're generating double the HP than that generated from say and "long runner" AEM. What may in fact be happening is that an increase in intake air velocity is making the throttle more responsive, which obviously feels like more power. Yet when one dyno's the various intakes, they all seem to very close in overall performance.

The very same principles behind a CAI are also applied to turbocharger intercoolers. Whether air or water cooled, an intercooler reduces the temperature of the intake charge to create a more dense environment, thereby forcing the fuel system to squirt more fuel and increase the volume of the combustible mix in the chamber...thereby increasing HP. Now let's talk volumetric efficiency...

jatt

your car works like an air pump.

man's ultimate goal is to get greatest efficiency out of their car.

basically, the more air you have coming into the car, the less restrictions in air flow, and more room for air to leave the better the car will run. by that meaning, getting more air = intake, less resistance to air flow = ported / polished head. more air out = headers, high flow cat, and cat back exhaust

LVXB

okay ill try to explain it the same way you actually asked.

there is only two ways of extracting more power from any given engine.

give it more air (if air is cold there is more of it in a given space)

give it more fuel.

an intake simply gives it more air.

woof

How difficult is the stock CAI to install? Can a couple of guys handle it? Any drilling required?

How much are the replacement air filters?

Looking mighty hard at an xB and this may be the only mod I'd use.

Thanks.

LVXB

well there is no "stock" cai since "stock" it comes with a standard airbox.

if you mean an aftermarket intake. well ive only had experience with the injen.
yeah its not a true cai (im not sure why) but its essentially the same. it took about an hour to install but it only would have been 35-40min had the instructions mentioned taking the battery out. if you have even a modicum of mechanical skill you can do it.
and for $150~ its hard to go wrong. if you want to pay $400+ you could get the aem at the dealer.

CBSIMONSEZ

Most any aftermarket intakes are user freindly. When they are designed, they take this into mind, that the owner is going to try and save a buck and install in their driveways. If your patient, and follow the directions, it should go in easily. Even my Iceman install on my NEON only took about an hour, with no drilling or modification, they just design them that way.

xbchance

Amazing guys, thanks for the wealth of info.

If you had your druthers, which CAI would you recommend? I just don't know why I'd put in the AEM if it only adds 2 HP [just what I've been told].

Thanks! :twisted:
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LVXB

thats a big cans of worms on this board so dont ask anybody to open that up. just check this forum and make your decision. im very happy with the competitively priced injen personally.
https://www.scionlife.com/forums/viewforum.php?f=6
just go through and check out threads.

CBSIMONSEZ

Me personally, i like the sound of them, and the little added boost. IMO the best bang for your buck ... InJen. You can get them as low as $140 shipped.

SoCalbBox

funny how no one has mentioned harmonics...

TheLeprechaun

While harmonics may make somewhat of a difference, there are many other mods that will make more of difference and cost less than the harmonically tuned AEM intake.


Has anyone dyno'd their xB? What kind of power are seeing at the wheels? How much of an increase in power are you seeing from various high-flow intakes (CAI and the like).

$400+ for an intake is insane if you ask me. Evern $200 for some bent metal with a filter on the end is damn expensive. What kind of sensors are inline on the stock intake? I'm coming from the motorcycle world - our fuel injection is 10 years behind automotive fuel injection. Every engine modificaiton I do requires the FI to be remapped.

What aftermarket intakes are available for the xB?

SoCalbBox

Like...

TheLeprechaun

How much power do you actually see on a harmonically tuned intake over a similar non-harmonically tuned intake?

If it were me, I'd rather purchase a CAI tuned to increase the velocity of the air and lessen turbulence by tuning by length and pipe diameter and then spend what I saved on remapping/retuning the ECU - maybe to run on premium fuel.

ScionPimpN

There are plenty of intakes on the market. Here are a few and what I thinks about them. I hope this helps.......

AEM- The biggest waste of money for our cars. At $300+ its about double the price of the other intakes and about 2 times less power. But looks the best in my opinion, and has a filter to prevent hydrolocking your engine. So if money is no option and you dont care about power, and just looks then the AEM is for you. I wouldnt spend my money on it.

INJEN- From what I gather the most popular. Among the top dyno prove intakes, as well as the most simple to install. Although not a CAI the simple straight short ram design alows good airflow. Being able to order it in different colors adds a good option for customizing and $130 isnt bad if you ask me.

WEAPON R- Havent heard alot bad now good things from them, all I know is that its about as cheap as the Injen and adds about the same horsepower. They're a company thats been around for a while,and have had a proven product for quiete some time.

K&N TYPHOONE-My choice as the best Intake. I have it on my car. At $160 shipped its amongst the cheapest. Its A CAI system which utilizes the K&N' new technlogy. Your not going to get a better filter on the market. You can get it in different colors. The only draw back is the install time which took my 2hrs, jacking up the car to install and intake isnt my idea of time but, proved to be worth the 6hp gain @wheels that I got from it. I would recommend it to anyone.

Of course there are many other intakes I just chose the more popular ones to give some info on. Research is the key, like the guys on the forum have said before, its all trial and error see what power guys are geting from the different intakes. Let them be the guinny pigs the you can purchase the one that suits your needs and budget. I Hope this helps!!!! -ScionPimpN- OUT!!!!!!