I want to switch back to my stock air box with a K&N air filter, does it really give you more power/gas mileage?

 

All it will do is change the sound and relocate some power down the rpm's. Aftermarket intakes only really "add" power if the car is tuned with it. The stock ECU has parameters that try to stay the same regardless of intake. So an aftermarket intake on a un-tuned ecu basically does nothing but change the tone of the engine. It will allow slightly more airflow for the top end at high rpm's, but doesnt help the power under curve. More or less the two are the same. So it comes down to personal preference of what your engine bay looks like.

Tuned is another story, and an intake matters.

 

running too short of an intake will hurt power in a noticeable manner. even untuned, a properly setup intake pipe will yield results. but this is typically done on a dyno during tuning sessions.

that's part of resonance tuning. there isn't a one size fits all when it really comes down to making power.

the aftermarket short rams are typically the same length and roughly the same size as the stock intake tube. you aren't going to be gaining anything just by swapping them out.

 

I do a lot of city driving so I would prefer some more power down low. I did notice with a short ram my engine is so loud if you step on it and you have a passenger talking to you you can't hear them at all lol

 

If you want power down low, buy a V8.

You have a 4 cylinder. Power down low, in literal terms, doesn't exist without spending money

 

My H23 makes enough torque to satisfy me. I don't have the kind of money or taste anyways.