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K&N Drop-In/Stock Housing Lid

9K views 27 replies 15 participants last post by  danbfree 
#1 ·
Hey guys, I have a question about the whether or not to leave the stock filter lid installed. I've done a lot of research on the forums and I am definitely going with the K&N drop in; however, I am still confused about whether to keep the lid on or not. I know there might be some heat issues with removing it and some obvious restriction if it remains... What do you guys think is best to achieve the most potential from the drop in? Thanks guys!!
 
#2 · (Edited)
The only potential benefit you will gain from leaving the lid off is noise. If you leave the lid off, the intake will be pulling hot engine bay air in, which you do not want. Leaving the lid on will be best for performance and will be much quieter.
 
#3 ·
I took mine off and am running the paper filter just because of what everyone was talking about. Left it off just for the sound. My opinion is it sounds great at WOT. I have my K&N on order. Should be here this week some time. Eventually, I wanna fab up my own lil heat shield design and actually get some hp and not just be a placebo.
 
#8 ·
What I did was I bought a new air box lid (only about $6). I drilled a 3" hole in the front left with a hole saw. The hole faces front and lines up basically with the hood/fender gap on the drivers side, the grill/headlight area. I think cool air penetrates. I made a shield on the top front with 2" foam (like you use on your house windows to insulate an a/c unit). I have a K&N drop in with that. So there is a significant additional opening (bigger than the throttle body) but some heat protection and a little more sound. It is a little louder but not ridiculous and I think I notice a performance increase. It can be easily changed for dealership visit or inspection. I see recently there is a UK company offering a filter with the top end opened (which would be exposed on our cars) or the make an adapter ring that can be used with universal K&N type filters.
 
#10 ·
Quick update, installed the filter earlier today and all I can say is that it feels like a new car!! Definite (but slight) improvement in power/acceleration/pick-up. Biggest improvement was how much smoother the car felt while driving. I have a 5 spd, gear changes felt way smoother and no "lag" feeling after accelerating from a full stop... Overall the engine performs/feels better. In my opinion replacing the stock filter is a MUST! Can't wait to see what will be avaliable for this car in the future...
 
#15 ·
Got mine yesterday [:)]



Like I said in my build thread, I doubted that I would feel a difference and I really didn't. There's alot you have to do to get colder air to the stock housing (ie newmission mod) and what ever. I really don't want to cut into it just yet. I will look more into a custom heat shield and what not, but for now it's good
 
#16 ·
You can also net a little bit more power by doing the snorkel delete with a flathead screwdriver and about 10 minutes of work. The dyno data is in my dyno thread and ZX3Matt has a pretty good information in a thread he started (which you can link to in my dyno thread).
 
#18 ·
Let me rephrase what I said...I didn't feel a difference because I've had this car for a week and have been running lid off since day one...lol Im sure the power is there, Im just not feeling it in the "butt dyno". Sorry didnt want to confuse people.

As far as the snorkel delete goes, I read that in your thread and was going to do it after work today [:)]
 
#22 ·
The best mpg's I've gotten were with the drop-in filter, lid on, snorkel delete, and flap cut (behind the d/s whisker). Anything before or after has been less for my commute. If I was making highway/interstate commutes then the Newmission I did after would probably be better.

Sent from my stupid phone.
 
#24 ·
Here's what I did to mine. Made an insert out of some chromed, decorative sheet metal, backed it with some screen, made a fancy cut-out, and bolted it in. Straight-up, it was too loud for me, so I've been experimenting with an insert that I can "tune" by varying the size of the cutout. Insert goes underneath everything, so it's not even visible. K&N Drop-in, snorkle delete btw.
Photobucket's freaking-out right now--I'll get a pic up later.
 
#27 · (Edited)
You have to watch out using other filters that are not supported on the far end, like the OEM and K&N filters are. The band that secures the filter to the MAF housing will not hold the filter forever, and you can't tighten the band enough to do so (the MAF housing will collapse).

I tried this, and ended up with a check engine light, poor idle, and surging throttle. I even started a thread about it.

Click Here

Seemed like a good idea at the time, since I prefer nano-fiber media over oiled cotton.





 
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