Hey guys, i want to get an exhaust for my LBZ. My buffy has a straight pipe 4" LB7 and it sounds like garbage and is too loud. I was planning on a MBRP Turbo back 4" (Includes a free flowing muffler). Any ideas? Could i go 5" while im at it, or will it make it a lot louder. I like the turbo "jet plane about to take off" noise, not so much the grumble.....

4 or 5" with a muffler won't be bad at all. You will hear it when you want, but it will be quiet all other times.

I love my 5" MBRP with a muffler, it sounds awesome. It's got a deep rumble, you can tune it out cruising and when you get on it, it'll talk.

MBRP is what I ran on my LBZ and it sounded great.

MBRP is a great system I love the one on my LLY. Its nice and quiet inside the cab and not that loud outside until you get on it. When I put my system on my wife said she couldn't tell a differance inside with the windows up. The air/jet noise comes from the turbo veins so the exhaust will not affect that sound much. Your buddies LB7 sounds different because he has a fixed geometry turbo