Well, lets start out by saying the e34's intake has been debated for many a year, as to whether or not to go cold air, or bust out a K&N in the stock airbox. Being the silly teenager I am, I opted for the 100 dollar powerflow kit, offered at bavauto.com. Great company, btw. After putt-puttin around for about 2 months with it in, I came across a racing enthuseist(sp?) and his e34 540. Inside that 540 was a K&N in the stock airbox, as he stated no matter how much airflow you get, if its hot, you lose hp. Keep in mind I have the cone setup, but i was also sporting a white trash can cut in half serving as a heat shield. I then took another trip to bavuto.com and bought myself a k&n for the stock airbox and put it in.
Verdict: The cone filter gave me an awesome sound, and better throttle response. The heat shield I made for it looks mad ghetto, so it lost points there. The K&N in the airbox looks nicer, but the sound faded, making my BMW feel stock, but the power was there. I have yet to really determine that the K&N in stock airbox gives that much more hp, but I like the look, so im keeping it.
I'd have to say they are pretty much equal, with one not having the nice sound.
What are you guys running, and what do you think of my experiment?
1990 535i 5 Speed +[E.A.T. chip/Powerflow intake/Tri-flo exhaust system/Strut Tower Bar/Smoked Signals/Pioneer Head Unit/Crossfire vr401 amp/12" Crossfire BMF sub/eyebrows/18" alpina replica rims]+
6 cylinders, 5 Speeds, 4 Doors, 3 Pedals, 2 Exhaust Pipes, 1 Ultimate Drving Machine