luckydawg003

I have just a few a ?'s about the cold air intakes....For one it looks like all of the gt c.a.i. are short warm air intakes....cause a c.a.i. is supposed to be low in the engine bay to get the cooler air coming under the car. And another why do all of them cost around $300 from what Ive seen most only come with a filter that fits right on the stock intake tube. What a rip off. 300 for a stupid filter. I bought my real c.a.i. for $100 for my eclipse.

shaners90lxhatch

Cold air intakes are BS. The "cold" air will not give you a noticeable increase in power, basically they provide an un-muffled, "un-restrictive" path for the air to take. Your intake air temp sensor determines if air temperature requires a change in fueling so its placement in the intake system is key. People often overlook the big picture. You don't want to trick you car into thinking it is getting more/less air than it actually is. The premise to ANY intake or exhaust modification is to allow the engine to breathe as much air as possible at any given moment AND be able to accurately measue that air's volume and temperature so that the computer can fuel it properly. There are performance benefits to warm air. Research Smokey Yunik's hot air injection engine and you will understand my previous comment. 250hp and 40mpg out of a 2.5 iron duke that has a stock 80hp and ~20mpg rating simply by heating the air/fuel mixture almost to the point of combustion. WAYYYY to much controversy on this subject but learn what is going on and figure things like this out on your own OR if you have to take advice - take it from someone who really, really knowns engine performance. There are a billion internet mechanics out there that don't understand the first thing about what is good for an engine. In other words, I know sugar is bad for my teeth but you don't want me giving you advice on performing a root canal

markj

Most of the reputable CAI folks out there have dyno charts to support thier HP increases. So that's the bottom line. In terms of real world performance you will be able to feel the difference. IMHO it's the best bang for the buck. But don't take my word for it look at the dyno charts.

scramblr

Yeah, Shane's pretty much anti-mod...which is cool if that's what you want. Some CAIs do only offer the filter to hook up to the stock inlet tube. These usually do not require a tune. Now, if you go with C&L or JLT, it comes with a larger inlet tube which does require a tune. Proven 20-30 hp increase which is not imaginary. Aside from the extra air, it is all in the tune.

CrazyAl

Like Shaners said, the REAL goal of an afternarket intake is to reduce the restriction of the intake tract. "Cold Air" is a common marketing term, but it's fairly meaningless. As you said, these things should be called "low restriction" intakes, not "Cold Air" intakes.

Placement of the filter is not particluarly critical. You mentioned that a CAI should be located down in the fenderwell...that's also a bit of marketing speak. How do you know that it should be in the fender well? Do you really think that when your car is moving that "fenderwell air" is going to be appreciably colder than other air around your car or engine compartment? Measure it in a few different spots with a thermocouple thermometer while you drive and you'll see soon enough that it doesn't matter enough to make a HP difference.

By the way, Smokey's "hot air" engine is a real can of worms. I belive that it WORKS, but understand that it may be very different than what you think. The laws of thermodynamics dictate that any heat engine (jet engine, 2-stroke piston engine, 4-stroke piston engine or diesel) will increase in efficiency as it's operating temperatures go up. That's why cars have high-temp thermostats from the factory and why older cars typically had a "stovepipe" on the intake, that would suck hot air from around the exhaust manifolds to heat up the engine quicker. Smokey's engine is taking a fixed amount of fuel consumption and is then getting a higher-than-normal amount of power out of it due to efficency gains from the thermodynamics of the 4-stroke process and also due to increased atomization of the fuel. Turbine engines used in power plants do exactly this same thing. It's called reheat.

On the other hand, cooler air (significantly cooler air) is denser than warm air. That means more oxygen molecules per unit volume. That means more fuel can be burned in the same size engine, which results in more power. This is not an efficiency improvement. In fact it is a slight efficency DOWNGRADE. However, you are getting more HP becasue you're burning more gas.

You can think of it this way. Three women are going shopping:

Mary has $100 (think of this like a stock engine)

Julie has $100 too, but she knows the store owner, who is willing to give her a 5% discount. That means she can actually buy about $105 worth of clothes. (hot-air engine)

Jennifer has $100, but she's also willing to spend some extra money off of her credit card too. (CAI)


Colder air WILL provide an obvious increase in power. However, getting cold air is another story!