K&N Drop in Filter vs K&N cold air intake

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K&N Drop in Filter vs K&N cold air intake

Post by kwak88 »

its a cost issue, one being like 40$ vs 200$...

im not looking for any significant HP gains, but in terms of MPG and cool SOUND, will the drop in filter do just fine?
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Re: K&N Drop in Filter vs K&N cold air intake

Post by vedran »

with the drop in filter, you won't really notice a difference in sound. i never have and i've put one in three different cars.

the CAI will definitely make your engine growl, though. you might get better gas mileage, according to their studies. you will be able to do this as long as you keep your foot off the accelerator. it will be hard to do because you'll want to keep hearing your engine roar with the new intake.

as for the price, you might want to just order an eBay CAI for ~$25 and slap on a better filter (~$30+). after all, a pipe is a pipe. as i've mentioned in a thread before, the only reason you'd need to spend $200 on a CAI is if you lived in CA and you needed a CARB sticker on the pipe to pass emissions or avoid getting hassled by a cop.
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Re: K&N Drop in Filter vs K&N cold air intake

Post by kwak88 »

daam 25$ for a CAI? where are you finding these prices?!

i have seen nothing under 170$, even from autopartswarehouse.com
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Re: K&N Drop in Filter vs K&N cold air intake

Post by vedran »

hmm, i had trouble finding some for that price, too. didn't look at your specific car before i posted, sowwy :( .

are you a part of a z forum? they may know some good places and have better suggestions for your car. i bought a CAI for my CL from eBay for $15 and it fit perfectly.

i know for some cars that have decent-flowing stock air boxes, people just add a small bent universal pipe (~$10-$15) after the MAF, run it down, and attach a filter at the end, thus creating a ghetto CAI.
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Re: K&N Drop in Filter vs K&N cold air intake

Post by theholycow »

If you already keep your foot out of the accelerator, intake improvements won't help. Intake improvements will only help if you're already producing your engine's maximum horsepower all the time.

Consider this: The stock intake with the stock paper filter must flow well enough to move all the air the engine pulls when WOT@redline (well, to be accurate, at whatever RPM it makes the most horsepower). Most driving, especially for someone who would want any kind of fuel economy, is done at far less than redline, and/or less than WOT. If the throttle is not wide open, then the throttle is by far the most severe restriction and the rest of the system doesn't restrict the resulting amount of air at all. Even with wide open throttle, the engine can only move as much air as can fill the cylinders, which don't need to be filled as often at less than maximum RPM...and even with the throttle wide open, the throttle is still the bottleneck anyway.

Common design compromises such as cost, noise, and emissions don't have much effect on intake. It doesn't cost much, increase noise much, or increase emissions to build the car with a larger intake or a larger filter. There's no reason to make it so small that however much air can be pulled through the throttle would be restricted in the filter or intake tube.

The engineers who designed your car aren't fools. They know how much air it can move when in stock configuration, and would be negligent to supply less than that. This is especially true from the point of view of fuel economy; if it can't efficiently handle passing enough air to cruise along making the 15-30hp to keep rolling along the highway, how is it ever going to flow enough air to make 150-300hp at all?

Exceptions would be if there's not enough space under the hood to do it cheaply (and your car is cheap), if they used an off-the-shelf airbox that was for a less powerful engine, or if your car is not stock. If you have an upgraded exhaust system and a tune, that's a different story. At that point you are limiting your top end with the stock intake, which was designed to flow as much as the stock engine needed and not necessarily more. However, you're still not affected fuel economy, unless you always drive WOT@redline.

Edit: I forgot to mention, if you just want it for the noise/look and were merely proposing fuel economy as an additional benefit....enjoy it. Just don't expect it to ever pay for itself in saved fuel.
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Re: K&N Drop in Filter vs K&N cold air intake

Post by Rope-Pusher »

If you can grab significantly cooler air, there may be a fool millage increase, but only slight. Nothing to pay off the investment with very soonly, eggsspecialty since iff hugh evva tromp on it, even just onest, the payback period extends "to infinity and beyond". Cold air intake can help with making some more horsepressure, if your intake currently draws in hot, stale underhood air. Plastic intake manifolds help in this respect too, compared to aluminum manifolds. Sins most folks go through their entire lives without ever having the acceleration of their vehicles measured, the greatest benefit to playing with the air intake is to increase the intake roar, so it sounds like you're making power. Unmeasured performance comes down to perception, and if the perception pleases you, you're there.
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Re: K&N Drop in Filter vs K&N cold air intake

Post by noob5,000,000 »

If you're basically stock and n/a, a drop-in will do you just fine.
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Re: K&N Drop in Filter vs K&N cold air intake

Post by watkins »

Boost = need for intake. WWOOOOOOSSSSSHHHHHHHHHHHHHH
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Re: K&N Drop in Filter vs K&N cold air intake

Post by PILL »

Rope-Pusher wrote:If you can grab significantly cooler air, there may be a fool millage increase, but only slight. Nothing to pay off the investment with very soonly, eggsspecialty since iff hugh evva tromp on it, even just onest, the payback period extends "to infinity and beyond".
You do realize that colder air will yield worse mileage right? Cold air may make more power, but it will hurt mileage. For mileage you will want hot air.

Trust the hypermilers and their infinite knowledge of fuel economy, I do.
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Re: K&N Drop in Filter vs K&N cold air intake

Post by theholycow »

paul34 wrote:Point is, the numbers are the numbers.
That one's tough to argue. Believing in a placebo is likely to work better than grudgingly doing what may work. Driver modification has far more effect than most car modifications.

In my research, the warm/hot air intake works great on some cars (Saturn S-series, for example, seem to universally work well with it), doesn't do anything at all on some cars, and on some cars it reduces power without increasing fuel economy.

Considering the low cost and lack of financial motivation for anyone to sell it, it's not some snake oil being peddled by a scammer; you can't buy one, you have to DIY. I would suggest that anyone whose mind is open and who wants to should go ahead and try it.

I'm too lazy to do it right. I tried adjusting my intake location a bit and got my intake air temperature to increase -- ambient +50 degrees F. It didn't seem to help, though I didn't track it well. It caused no reduction of power in my car.
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Re: K&N Drop in Filter vs K&N cold air intake

Post by potownrob »

vedran wrote:with the drop in filter, you won't really notice a difference in sound. i never have and i've put one in three different cars.
when i put a drop-in k&n filter in the maxima i noticed the engine more and throttle response was improved. i think it also depends on the stock intake; if the stock intake piping is restrictive to begin with, a drop-in filter probably won't help much at all. Not sure how it really helps in my car, but it helps me to hear the engine a little so I don't have to guess when to shift like when I first got the car (of course I was going from a modded Civic :lol: ).
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Re: K&N Drop in Filter vs K&N cold air intake

Post by Rope-Pusher »

paul34 wrote:
PILL wrote:
Rope-Pusher wrote:If you can grab significantly cooler air, there may be a fool millage increase, but only slight. Nothing to pay off the investment with very soonly, eggsspecialty since iff hugh evva tromp on it, even just onest, the payback period extends "to infinity and beyond".
You do realize that colder air will yield worse mileage right? Cold air may make more power, but it will hurt mileage. For mileage you will want hot air.

Trust the hypermilers and their infinite knowledge of fuel economy, I do.
Everyone realizes that. In theory you're right. However, there isn't too much explanation for the increases people get with less restrictive intakes and filters, given the same non-aggressive driving. It could be that maybe they drive MORE gently now because they don't want to burn more gas... who knows. Point is, the numbers are the numbers.
I don't know that in the daze of fool infection cold air will worsen the MPG. With carburetors, that may have been the case, because you had a wet intake manifold and you needed some heat to avoid manifold icing, fuel puddling, etc.
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Re: K&N Drop in Filter vs K&N cold air intake

Post by ptsmith24 »

paul34 wrote:Well I think its that cold air is more dense, and thus, should require more fuel since there's more air.
But does the colder, denser air yield more power? If so, you could get the same acceleration effect with less throttle.
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Re: K&N Drop in Filter vs K&N cold air intake

Post by theholycow »

ptsmith24 wrote:But does the colder, denser air yield more power? If so, you could get the same acceleration effect with less throttle.
Yes, it does...Why would getting the same acceleration effect with less throttle help fuel economy?
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Re: K&N Drop in Filter vs K&N cold air intake

Post by ptsmith24 »

theholycow wrote:
ptsmith24 wrote:But does the colder, denser air yield more power? If so, you could get the same acceleration effect with less throttle.
Yes, it does...Why would getting the same acceleration effect with less throttle help fuel economy?
Less throttle = lower amount of fuel injected, correct?
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