Exhaust question 6.2 muffler better than 07 max muffler!!!
 

Does a stock 6.2 muffler flower better than my 2.75 stock 07 vortec max muffler????/IF I PUT 1 7/8 HEADERS LT ON WITH A FACTORY 3.5 6.2 EXHAUST OM MY SUPER CHARGED 2300 6.0 MAX WILL I GAIN 30 HORSE SEEING IM SUPERCHARGED,WILL I FEAL IT IN THE SEAT OF MY PANTS!!!ONE MORE QUESTION IS A EXTENED CAB SHORTBOX EXHAUST THE SAME AS A CREW CAB TRUCK I HEARD ITS THE SAME WILL IT USE SAME HANGERS THANKS GUYS

You will gain at least 30 HP. Your gain should actually be significantly more if you re tune it for the headers and get a pulley to bring boost back to where it was pre headers. I would honestly expect 50+ on your set up from a swap like that. How much boost do you currently run?

The gain will come from the headers your stock vmax muff flows excellently but the 3.5 won't hurt since you are FI.

Turn the damm caps off please. It hurts to read the post.

What size throttle body do you have? Call me crazy but I dont see a point on going bigger exhaust when the TB is still the stock size and first has to pull air through it.

Iirc they're at least 87mm but I thought I seen somewhere say they were 90 on the vmax. Correct me if I'm wrong. Ik my 07 max has a pretty big tb.

No...the TB is almost never a restriction, especially in a FI application.

I have like 8psi, when u floor it but kinda goes around 7.2 7.8 psi.I have a ls9 cam also in my truck with ls7 lifters.I think these motors are 9.1 should i boost up the psi i drive it on weekends, kinda daily driver how much boost is safe, normal i love the extra power WHEN NEEDED i drive it sensible until i get a anxious ford on the side of me LOL.these have a 90mm tb

Supersub would disagree and I think he has some pretty good testing to back him up at least on FI that sucks.

I got some pretty good gains going to a larger throttle body as well.

But if the setup was a blow-thru, I would agree with Atomic.