Thanks, I didn't see a lot of info about this anywhere but it's real low hanging fruit for the V6's since it doesn't require any welding and it allows the use of any GT catback system including an OE take-off.
The stock V6 exhaust necks down to a single 2" pipe which any internet exhaust calculator seems to agree flows enough for just about 140hp worth of engine before imposing much restriction. What constitutes "much restriction" of course is up for interpretation.
The cats and pipe before the Y are 2.25" and the Pacesetter adapter + catback are 2.5" so I think it's safe to say this is plenty for anything a naturally aspirated 3.8 will ever be doing.
I do have a race computer (Beltronics Vector FX2) and have recorded several "Before" 0-60 runs of 9.77 to 10.13 seconds, which old magazine car reviews confirm is about what they measured at the time. I've only done a couple preliminary runs since this was done because snow, in particular the stretch of road I did those previous runs is outside of town and slow to clear.
Butt-o-meter tells me it's a whole lot nicer above 3k RPM & these externally balanced V6's redline before 5k so there's only a limited amount of juice to squeeze up there.
The sound from the Force-II system is pretty good too, mellow with no drone. I kind of wish I had the $$ for a 2nd setup to put on my 5.0 that thing drones like crazy.