K&N panel vs. cold air intake
 

Does anyone know real world numbers or a rough estimate on the power difference between a panel K&N and a cold air intake on a stock engine? If its 1hp, then I'd rather have the reliability of a panel filter. I also heard you get really good gas mileage with the cold air, is that true? Thanks

My opinion would be biased. But IMHO, I prefer to squeeze out every hp possible. Especially on an engine like ours, where hp is not easily or cheaply added.

On a dyno I think you might notice a 2 HP difference at most, so if power increase is the deciding factor for you then a CAI would be a waste of money to you. Now if you would like to make the engine look a little cleaner and less cluttered, and enjoy the whooshing sound of an intake .. then it might be worth your money after all. Plus, you get a teeny tiny bit of HP added.

What about the Gas mileage
 

I'm about to buy a 04-06 Mazda 3, and I would like to know how the gas mileage would be effected if the MazdaSpeed Cold Air Intake was installed on the 2.0 engine with auto transmission? Also, when you said swooshing sound, what do you mean? does it make the engine sound "tricked out" and noisy? I wouldn't like that. The only other thing I want to do is get lowering springs and stabilizing bar kit, neither really affect the engine performance or gas mileage.
Anyway, I know I'm all over the place, but I just test drove an 06 yesterday and was EXTREMELY impressed, and quite surprised. If anybody owns one similar (lowering springs and stabilizing bars) and would like to just rant about it, I would totally appreciate it, and would love to know how the upgrades increased cornering and handling. I’ve also hear some negatives about highway speed noises and vibrations and such. Is that true?

You may actually need a "Looking to buy a 3" thread for this but the whooshing sound doesn't make it sound tricked out but ricers may ask if you have a turbo. Happened to me a couple times.

I noticed an improvement in gas mileage from installing an intake and exhaust. You may only need an intake as the exhausts are pretty descent on the 3's.





KevinProtege5,
I am not sure about much if any hp increase but I did notice an increase in torque and over all gas mileage.

Ill tell you, the cold air intake almost sounds like a deep exhaust when you get into the pedal

Cool
 

Thanks for the info, deep sound is ok, and better torque with better gas mileage! If thats true I'll get one for sure (intake). Thats good I won't need an exhaust upgrade as well, I would like to limit the upgrades as much as possible. I'll check out that other thread too.