Here we have a cool comparison for you. It is a 09' Ford F350 with a 6.4L compound turbo and a stock H&S tuner Vs a 2011 Silverado with a 5.3L, LT headers K&N CAI, 373 gears and Drag Radials. The race is close with the Chevy taking the first run.
Then they modify both: The Silverado beefed up with a 228R Cam, D.O.D/.AFM delete kit, VVT delete kit and retuned. The Ford added a 4 inch Diamond Eye Exhaust and a tune. The results may surprise you.