Review on K&N Cold Air Intake Kit: Boost Horsepower with High Performance Guarantee: Legal in All 50 States: Fits 1999-2005 BMW 3 Series (325Ci, 325i, 325xi, 323Ci, 323i, 328Ci, 328) 2.5/2.8L L6, Part No. 57-1002 by Craig Sethuraman

Probably lied about the mileage. Just because I'm speeding around town with the windows down to listen to that sweet, sweet 3km deep rumble followed by a burst of air that allows for better throttle response. When I hit the freeway I notice a jump in mpg, not much but over time I'm sure it saves money. I also notice that I don't have to downshift as often when accelerating. He's confident in the gear I'm in. So it's easier on your transmission for the average driver. I hooked it up to my obd2 scanner both before and after installing this inlet and the numbers show that initially the engine temp is higher (throttle temp). This is to be expected when stationary or idling. But once you start moving, g. The air temperature drops significantly. And when you put it down, be careful. I saw the temperature go from 115C to 82C in moments after I hit the ground and changed gears. This is good and worries the road users. I can suggest a performance filter instead of this intake system. It doesn't bother me, I rarely sit where I live for more than a few minutes. In general, I like this system. It is easy to install with basic shop tools and sounds better. I'm not entirely sure my mileage will ever improve (lead foot). But it is clear that something must be said about the airflow under load, which lowers the air temperature. And every car enthusiast knows that lower air temperature, higher compression, more power. Spend your money and see for yourself.