(THIS INSTALL IS THE SAME FOR A 7.5L 460 AND A 5.8 351W)installing a s&b air filter (kf-1014) on my truck. honestly i think i gained a mile or two in fuel mileage, and as far as horsepower i personally dont think air filters add power, i just got this one to clean up my engine bay and make it look nice BUT i do notice a slight pick up in power when driving. i get up to 50mph Farley quickly now and for a inline 6 thats not to shabby because these motors are know to be slow torque beast