lets see air filter,ez=around $500 (actually less if you shop around). 4 for 4 on hemis. then came the 4 inch. but they have duals so we spent money there, both of us. with the injectors(only 40 hp)@ $800 they are only wishing. twins in the future are they dreaming,probably. moral for 500 bucks a hemi is no problem ,as for the extra money on the motor its like 5,000,not 10,000. do the math it only takes 114,000 miles and the fuel savings will pay for the engine all while beating up the hemi. that includes the extra on oil changes the cummins has. I say to each their own. keep on beating them hemis guys. got to keep the cummins respect,LOL.