WOW that's a trippy exhaust haha! Love the cutout. Are you the stock 5.3? I don't recall. I played around with running just my cats, and had bad results on the trail. My low end torque was gone, and my gas mileage was worst I've gotten. My 6.0L build is really sensitive to backpressure.
Did you notice any adverse effects to power w/ the cutout?
Mods in sig.
I've noticed no adverse effects. I'm 80-100 HP stronger according to my before and after 1/4 mile times yet I get the same or better MPG as I did stock with AFM. Cruising at 70, I opened and closed the cutout and saw no change in my instant MPG as indicated on the dash. So,
efficiency seems to be unaffected. As far as power, I'd
assume there's a minor loss of low RPM torque. Probably nothing I could feel or see if I did back-to-back runs comparing closed and open. I'd never be able to tell if any changes were due to the cutout status or the other variables involved. My mufflers are 3" and it tapers down to 2.75" after it goes over the axle. So, it basically mimics the stock design, just one step larger and has free-flowing mufflers. I'd say the muffled side is barely any more of a restriction than the cutout side. Ideally, on the strip, I'd start with the cutout closed and open it around 3,000-4,000 RPM. Pretty much the same idea as the active exhaust on the Corvette. The single digit gains, if any, aren't worth the hassle.
