Everyone



Thinking of putting a K&N box filter in my TII. Any benefits or draw backs? Does it increase boost, or cause the engine to run leaner?



Spike

I did not notice any difference when I swapped the stock element for a K&N drop in element for the stock airbox. I suspect it improved airflow a little, but not enough to affect your car's ability to cope with it, IMO.



Now removing the stock airbox and putting on a K&N cone filter, that's a whole 'nother ball game. No other single mod I've done so far had anywhere near the impact of getting that airbox off. I suspect you'd need at least a FCD if you went that route, and you'd better keep an eye on your A/F ratio.

if u go witha drop in k&n you should gain about .5 psi more on an otherwise completely stock car. that is what myfriend have gotten on his s4. thought he said it wasnt really a noticeble gain.



if you decide to go with a cone style intake get the fcd since you will be hitting fuel/boost cut.

performance gains aside, a k&n is a good thing because you don't have to keep buying filters, you can just clean and replace it

I picked up a used one from ebay (fipk) and installed it in about an hour, my car was hell to start right after i got it on, I think some of the cleaning solution was still in the filter, and my exhaust popped a few times (just like a few puffing sounds followed by a doughnut of exhaust gasses), now it runs fine, no more popping, I can hear a little bit of a difference beneath the hood, but I imagine I need to fabricate a heat shield before I'll notice any real differences. It does seem to pull a little bit stronger up hills than it used too, but I'm still drag limited at 110. :P

Get a cone filter. Effects of the cone filter: You might notice a small difference in power, but most likely not, you will hear your turbo spool a lot louder, and thats about it. You wont even be close to fuel cut. Now if you put a 3" downpipe and midpipe on then you would need the fcd. If your planning on increasing the power of the car by any significant amount, just start saving for a Haltech, It'll make everything a lot simpler in the long run. Stock ecu doesn't like much else but stock.

Can someone fill me in on what the FCD is?

keeps the computer from cutting the fuel from the motor at like what- 6.5 lbs? needed for anything thats gonna increase boost levels in the motor.

^ yup, fuel cut defender.

yea, getting a cone filter wont make much of a difference, it will just let your engine breathe alot easier.