Yes IAT makes a difference with a N/A motor so a true C.A.I does offer significant gains when compared to an intake in the engine bay. However, on a motor like ours the air is going straight to the turbo's where about 1/2'' away is the exhaust manifold, hot sides of the turbos, etc. So cool air is not going to make much of a difference because no matter how cool it is once it goes by those turbos its just going to get heated right back up. Thats not to say we dont benefit from cooler air comming in but it has to be a SIGNIFICANT difference to add any sort of HP compared to an N/A motor. A turbo motor like our will benefit more from an efficent FMIC then a C.A.I. Get an intake that breathes as good as possiable and then get an efficent FMIC.
I dont know if you can say an intake doesnt help. Go for a jog with a straw in your mouth and only breather out of that. Then go for a jog and breathe out of your mouth like normal. You tell me which is easier.
Originally Posted by SennaZ
Nice piece of work ericsmc83 which basically confirms what I've been saying for some time now.
Intakes, in general, are not going to produce a whole lot of gain - any company claiming 27 hp should be avoided like the plague.
Any road racer will tell you that it's all about intake air temps. Doesn't matter if your ride has a "tune" or not - unless you're talking about 500+ hp.
However, a "dyno for hire" is not going to have the 80+ mph fans necessary to test ANY air intake system. Dinan and others could prove to be a real resource here (they have those 'wind tunnel' kind of fans).
So where to go from here? IMHO, look at a true CAI system, try to find a dyno test facility with the 'mother of all fans.' AND, be happy with BMW's performance intake claims of +3 hp @ 6000 rpm. IF you can find a system to match or slighly beat that, you're doing about as best you can.
As an added note: notice that the BMW engineers didn't go with a cone or for that matter, a dual-cone setup, but just went with a secondary source of cold air. Unfortunately their CF setup will probably run close to $1K, but maybe the aftermarket guys will come up with something less exotic looking and at a lot lower price.