I'm assuming this is a pretty simple answer, I just couldn't find it anywhere, so I thought I'd ask the all knowing minds here. I recently bought a bully dog and tuned my 2014 2500. I am about to throw on a turbo back exhaust. I know I need to tune it for it to run with the new exhaust, but do I need to retune it after I have the exhaust on, or will the tune already do what it needs to do even though I tuned it before the exhaust was on there? I'm thinking that it's a set tune from the bully dog, so it shouldn't matter if I did it before or after, but I'm just hoping someone can give me a definitive answer. Thanks in advance guys.