Originally Posted by madmanhiker
You are going to get more Injen votes than the aFe not due to "preference" but rather due to the fact that Injen came to market nearly 7 months sooner
than the folks at aFe. That fact will cause a statistical variance, thus your poll will not accurately represent the answer you are looking for.
I can tell you that (for the n55 motor) the stock air-box is fine. Adding the aFe drop-in will help increase airflow; this has been proven by MAF and CFM analysis. I personally went with the aFe drop-in when it first came out, but I was not impressed. I did NOT dyno the difference between stock and drop-in. The aFe was in design for what seemed an eternity but they finally released it I believe in late April this year. I went with the aFe cai based on previous experiences with aFe products; they have an excellent build quality and they typically have very good results. I DID dyno my vehicle after the cai - not explicitly to test the cai, but rather I was troubleshooting heat-soaked runs on a hot day of dyno's. I can tell you that the aFe claim of HP gain falls short of the manufacturers claim, of which I brought to their attention, I can tell you that it DOES add power -about 10 rwhp. That was proven after several runs without and re-installing.
Read and more importantly - SEARCH the forums - the cai for the n55 has been posted and talked about for nearly a year now. Hopefully my post will shed some light on your current query and you can now continue on your journey to enlightenment.
Good luck and God speed.
I'm new here, just collected my 2011 E90 335i a week ago. Since then the only two mods i have done are window tints, and the AFE stage 2 intake.
I'm a big fan of intakes, and although i actually tried out drop in intakes in my previous cars, i always ended up with a full intake system.
To be honest, i went with AFE because im near to Turner Motorsports, and they carried AFE products, and could do the install for me as well. So for the savings in shipping VS Injen, i went with AFE. The Injen intake would have been cheaper, but honestly should i have had the choice, i would still pick AFE, as their design seems a lot more well engineered.
I drove my car hard around and empty stretch of road after the install, and my engine was really hot, but the piping for the intake was amazingly still cool. Hence the one definite gain i can share is that there is little to no heat soak.
Performance wise, the car became a lot more lively and responsive to my throttle input, i was surprised to find that there was less turbo lag, and the low end pull was noticeably(not significantly) stronger. Up through the revvs, the car felt the same, but the engine note was awesome.
Speaking of sound, the AFE intake DOES make the "woosh" noise. Its loud enough that you can hear it at all speeds with the radio off, and for your passengers to notice it and ask about it, but NOT loud enough that it sounds like a JDM racer. You can now hear the turbo spooling as well which is something that i really enjoy.
Here are some pictures(camera pics). Let me know if you would like more information. It has only been 4 days since i installed the intake, but it has really transformed the way the car drives and sound. To be honest though im not sure there is an increase in HP. Maybe TQ.