air intake question

[matt4pl]

i think this was covered somewhere in the forums or elsewhere, but i cant really find it anywhere, so maybe i cna get an answer

how exactly does an air intake (cai or ram or whatnot, aka aftermarket) improve gas mileage? it get more air in, and its colder/denser, so that would requier more fuel to be injected to ignite, right? correct me if im wrong, but i'm planning on getting an intake and i want to improve mileage, so im wondering, thanks, matt

[Calvin]

- (1) - I don't know if those claims of improved gas mileage have ever been proven.

- (2) - The theory is that your motor operates more efficiently overall when it breathes easier. 4-stroke engines only produce power on every fourth stroke. Intermediate stokes -- sucking air and blowing exhast -- consume power. Also, to the extent that a CAI allows more air (hence more fuel) to flow into the cylinder, that translates into more power on the compression stroke and ultimately at the wheels. Which in theory means that you don't have to push down as hard on the gas pedal as you used to. So as long as you resist the urge to stomp it.... (yeah, right)

[Mayhem_J30]

If it does improve gas mileage it'll be a very negligable amount. But always remember this, when you're increasing air flow into the motor it has to be at the sacrifice of something...filtration. Something many of us tend to just accept but it's always there haunting ya.

[Trigger]

ok here is what i would like to know. I have a 90 240SX and i would like to get intake on mine. I have the KA24E motor ,i believe, and I can't seem to find anything for it. Can any of you guys or girls help me out here.

[Calvin]

Mayhem_J30--

Its a valid concern, but I wouldn't assume an answer without empirical test data. Cone filters have gauze instead of paper, oil impregnation, and a whole lot more surface area. All this makes for comparing apples and oranges.

Want an analogy?: Keeping bugs out of your house depends on the quality of your screen, not the size of your window. Nonetheless, a bigger window gives you more airflow.

Trigger--

Your best bang for the buck is probably either Injen or Hotshot. They are basically the same. Both give you a larger tube over the radiator and a cone filter on the end. Injen was dynoed by SCC with some impressive gains. Both will run you about $200 new.

[matt4pl]

right now i'm driving the car to school every day and on the weekends, and i don't make a huge lot of money. i'm going to get some platinum NGK plugs or something of that sort and some new wires, probobly accel, dunno yet. i'm also going to seafoam the engine and clean out the throttle body. its got 120k miles, so its been used a lot, i want the extra HP of an intake, but if its actually going to decrease the mileage i'm gonna hold off until i can keep up with the gas. my money is needed elsewhere. also, how do cat-backs and headers affact mileage?

[A5295]

I am new to this site, and was wondering-i built the intake for my maxima myself, would i be able to do the same thing with my 240?

[trpower7]

Ok, to answer some of your questions:1) It's mostly heresay that says an intake will give you any kind of noticeable horsepower OR gas mileage increase. Mostly what an intake will do is make your engine breathe a little bit better, but your stock intake system isn't really breathing hard until around 4500-5000 RPM. And even at that level it will probably give you VERY minimal increases, IMHO not worth $200. You probably will notice some gains when intake is COUPLED with exhaust, but either or really doesn't net much.2) NGK platinum plugs are a WASTE OF MONEY ON A STOCK KA. Use what the factory recommendations are. A spark is a spark, in an NA engine as long as it's gapped correctly it doesn't need any more than that. It would be worth your money to buy new factory NGK plugs, gap them correctly, and put on new NGK wires. It's proven to be the best combination. And doing so isn't a power ADDER, it's just bringing your car a little closer to factory specs, I'm tired of people putting "Platinum Plugs" and "Performance Wires" on a list of mods.

[s14kaibigan]

I dunno if this goes for the S13 ka24De, but my S14 KA requires platinum plugs and they came factory. I grabbed the Densos for $40/set rather than paying nearly $80 for the NGKs. Didn't notice a difference either way except that "New Spark Plug Feel."j/k:)

[Nismo_Freak]

I paid 10 bucks for my set of Denso Platinums... screw payin 40 bucks for NGKs.