Okay, This is for Katsbimmer who was asking for help where the thread was closed by the Moderator (No flaming please):
This was taken from a e90 forum that I would like to share with Kats if she haven't done it yet.
This was taken from a e90 forum that I would like to share with Kats if she haven't done it yet.
superbass said:
Hey everyone,
I finally installed the K&N air filter tonight and here's my findings. First, as an installation note, you MUST remove the entire air box housing from under the hood. I didn't know that at right away, but it became pretty obvious after a few minutes that there is NO WAY to reach the Torx screws that are on the BOTTOM of the air box. Removing the air box requires removing two bolts that hold the top of the air box to the frame, then you have to detach the front left part of the air box from a rubber "accordian" leading from the air intake. Then you must loosten a round metal band clamp that is holding the edge of the rubber air hose leading from the rear of the air box to the throttle body. All in all, this process took me about 45 frustrating minutes because you have to wiggle and twist the air box carefully to free it from the rubber hose. Once you detach the box, then it's easy. Remove 6 Torx screws, take the air box lid off, remove the stock paper filter and drop in the K&N filter, screw it back together and put the air box back in the car.
Findings/observations
After putting the K&N air filter in, I started the car. There wasn't any discernable difference in engine sound or muffler sound when I revved up the gas, so I took it out for a little test drive. Well, here's the good (great) news. I felt that the car instantly had a little more pep, and also there was more of a "whooshing" sound when I got the RPMs past 5500 up to redline. I never heard that sound before, as I have been making careful observations about certain sounds and stuff ever since I got the car about 1 1/2 months ago. You really have to lay into the gas to know what I mean. When I was in 2nd gear, I really mashed the gas, but not all the way to the floor, and the car was really moving. And as I was mashing the gas, I decided to step the pedal all the way to the floor and there was like another sudden "surge" forward and the car accelerated even harder... weird!!! It felt like a downshift, but it couldn't be because the car was still in 2nd gear only! I guess the extra airflow from the filter caused the car's computer to change the air/fuel ratio and burn more gas. After, I returned from my little test drive, I noticed a different smell coming from the exhaust. It wasn't a bad or burning smell, but just different than I was used to. I've driven the car pretty hard before, but afterwards it never smelled like that.
Conclusion
I think that my $50 was well spent on the K&N air filter. I felt more performance, and got a little extra sound when you really mash it. Everyone should definitely think about dropping in one of these things.
I finally installed the K&N air filter tonight and here's my findings. First, as an installation note, you MUST remove the entire air box housing from under the hood. I didn't know that at right away, but it became pretty obvious after a few minutes that there is NO WAY to reach the Torx screws that are on the BOTTOM of the air box. Removing the air box requires removing two bolts that hold the top of the air box to the frame, then you have to detach the front left part of the air box from a rubber "accordian" leading from the air intake. Then you must loosten a round metal band clamp that is holding the edge of the rubber air hose leading from the rear of the air box to the throttle body. All in all, this process took me about 45 frustrating minutes because you have to wiggle and twist the air box carefully to free it from the rubber hose. Once you detach the box, then it's easy. Remove 6 Torx screws, take the air box lid off, remove the stock paper filter and drop in the K&N filter, screw it back together and put the air box back in the car.
Findings/observations
After putting the K&N air filter in, I started the car. There wasn't any discernable difference in engine sound or muffler sound when I revved up the gas, so I took it out for a little test drive. Well, here's the good (great) news. I felt that the car instantly had a little more pep, and also there was more of a "whooshing" sound when I got the RPMs past 5500 up to redline. I never heard that sound before, as I have been making careful observations about certain sounds and stuff ever since I got the car about 1 1/2 months ago. You really have to lay into the gas to know what I mean. When I was in 2nd gear, I really mashed the gas, but not all the way to the floor, and the car was really moving. And as I was mashing the gas, I decided to step the pedal all the way to the floor and there was like another sudden "surge" forward and the car accelerated even harder... weird!!! It felt like a downshift, but it couldn't be because the car was still in 2nd gear only! I guess the extra airflow from the filter caused the car's computer to change the air/fuel ratio and burn more gas. After, I returned from my little test drive, I noticed a different smell coming from the exhaust. It wasn't a bad or burning smell, but just different than I was used to. I've driven the car pretty hard before, but afterwards it never smelled like that.
Conclusion
I think that my $50 was well spent on the K&N air filter. I felt more performance, and got a little extra sound when you really mash it. Everyone should definitely think about dropping in one of these things.
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