Over 500hp.....3" exhaust...or 2.5"?

[lakeroadster]

Awesome pharmd! If that video doesn't make you grin you need to check your pulse.

[383 Stroker]

3" exhaust with x-pipe and flowmasters.

YouTube - Ernie's 67 C10 Idle & Rev

[1LOW4X4]

Definetely 3". My 5.3 only has a good tune and some other bolts ons, and I put Stainless steel dynatech LT headers on it/no cats/ and true 3" duals all the way to a big honkin dual in and out stainless Magnaflow.

These LS engines are my hobby first (with the older 350's second) and you want to go with 3" for sure. Let her breath, esp with all that hp. My buddy has a 2001 reg cab silverado with a stock shortblock 6.0, LS3 heads and FAST intake and FAST 102MM throttle body, and a 150 shot of spray, running 10.6 in the quarter, and its a daily driver.

He had Dual 3" and another guy convinced him to replace it with dual 2.5", that truck never ran as good. Sure, with a stockish motor, 2.5 is fine, but when You're packing ponies, you need the breathing room.