I'm not convinced by any of the systems that they better or not. So many systems are open to the engine bay air or they try to suck out of the fender well which is basicly sealed from a fresh air flow. Cummins spec for best mileage is 70 degree intake air. I was reading and PM'n a guy on the Cummins site who has a gauge for intake air and a manual vent to control the temp. I still believe in the cold air idea. My system is home built and 4" from the grill to the turbo. This was seat of the pants. The turbo can spend more energy pushing instead of sucking and its free air, just drive into it. Oh Marc, if your reading this, is there any info in the Ford family on intake temp?