The K & N web site has the formula for square inches of filter to hp for no loss. If I recall it is 7 hp for each square inch of filter using the K&N type. I bought a 6 x 14 for next year. I learned the hard way it is impossible for the most part to aviod getting some dirt in the motor. When I saw the dirt film in the throttle body that did it for me.


8..603 156 mph best, 2905 lbs 549, indy 572-13, alky