For my Christmas present I purchased an SCT X3 Power Flash with custom tune from Henson Performance. There has been a lot of praise posted on this forum about James Henson's tuning knowledge and customer support. From my experience to this point in the custom tune development process the praise is warranted. James has been very responsive to my performance requests and my numerous questions. He has drawn on his extensive knowledge to provide a tune that enchances performance while maintaining and even improving driveability compared to the stock PCM program. My 2000 SOHC engine, transmission and rear axle are completely stock except for the air intake system that consists of a Spectre high flow cone filter with 4 inch diameter outlet feeding a Ford Lightning 90 mm MAF sensor. The 4 inch diameter intake tube reduces to 3 inches just prior to the Ford 75mm ported and polished racing throttle body. An adapter transitions the 75 mm throttle body outlet to the 65 mm upper intake manifold inlet. The photo below shows the intake system. The PCM utilizes the voltage output from the MAF sensor to calculate engine load. Increasing the MAF sensor diameter from 55 mm (stock) to 90 mm results is a large decrease in sensor output voltage for any given airflow. Therefore, a custom tune was required to prevent engine damage due to an excessively lean fuel mixture.