We developed a formula once for how to determine the HP additions from bolt-ons: Add HP of first new part to base HP. Add HP of 2nd new part to gain claimed by first new part. Divide by 2, add to base HP. Add HP of 3rd new part to amount added above. Divide by 2, add to base HP. Repeat for additional bolt-ons!
Agreed, my runs were done a Dyno Dynamics dynamometer. The guy running it with over 11 years dyno experience told us that these dynos are the most reliable and repeatable of any dynos he's ever used. My pulls showed the gains they did with the K&N and I have no reason to refute or doubt them. But the K&N naysayers always will. Maybe they won't show a gain in every appplication but in mine it did. Kenny K.