Originally Posted by andrey_gta
Look up user Pushkin, he had a dyno of his injen. Some gains up top
If you are concerned, I think you can modify the Injen heat sheild to be more closed or have more air funneled to it with a flexible hose from the lower bumper grilles
Myself, I sourced a used eurobox from sweeden for a price around 250 shipped plus the cost of Afe Dry euro filter. If you are interested in the source, look up my recent posts in the "No 128i love thread"
And how was the car dynoed, open hood, and fans blowing? Yes you might see a slight performance increase since you will be getting plenty of cool air into the engine bay, sort of like if you where driving at high speeds. Now run the car for a while on a hot day and try to take off at the light and watch how sluggishly the car will run with the CAI.