I'm one of those "changed to headers but did not change the Y-pipe and change to the 3" tubing", and I'm one of those that report no significant changes. So like said earlier, I can only report my results. Given the post about results with headers/Y-pipe/3" tubing, sounds like he has a lot more experience with the 4.7V8 than I have experienced.
This is the kind of info I'm after.
I haven't priced out the upgrade Y pipe, but I'll guess it's not cheap either. We aren't building a race truck, just looking to upgrade to make a more fun to drive truck. We already ditched the factory muffler with a 2.5" Dynomax Super Turbo muffler. That gave her some much needed attitude, and my girlfriend loves the sound! I was pleased with the bark it has, even as a single exhaust still. I guess I'm still used to the sound of them on tired, smogger era 318s!
