This is true. I've toyed with the idea, but the BMW's OEM is actually a true CAI. The photo of the filter sticking up in the engine is pulling in hot air like crazy. That would normally pull timing and cause a loss of power. Not to mention losing the true cold air charge. Anything not mounted down in front, or in the case of the BMW, down in the fender, like the OEM, will only suck hot engine air like crazy.+1 the e39 already has a somewhat ram air cold air intake. The intake box takes in air from the fender and from the lower bumper grill.
Even Dinan doesn't claim that a cold air intake by itself yields a horsepower or performance increase.
Interesting. Do you think this may smooth out the overall airflow on the intake, or add a little more induction of air? I don't like that accordion section on the intake, or the intake "muffler", no bueno!If you want some more sound you could replace the postman hose with an e46 one to delete the sound resonator and remove the two air directing horns inside the airbox and remove the flap from the bumper tubing. Haven't tried this but was brainstorming a while back.
Interesting you mentioned airflow. Qsilver or edjack or someone in the last cai thread posted why certain parts where designed and implemented. To summarize it's to get airflow to hit the filter with as little turbulence as possible.Interesting. Do you think this may smooth out the overall airflow on the intake, or add a little more induction of air? I don't like that accordion section on the intake, or the intake "muffler", no bueno!
I like the OE CAI, generally, but I'd like to clean it up some too, possibly find a way to suck more air without a new system. Since I don't know BMW's, is there another model that I could take parts from for my 1999 540I to improve the intake? Wish I had the M5 setup...Thanks.