4MMM

I will be getting my 05 GTO with a Maggie soon. I am now into the header selection process. What gains should I expect after the Maggie install on a stock LS2? Should I choose the 1 7/8 or the 1 3/4? I might go with a slightly larger cam after that.

TheBlurLS1

iTrader: (8)

Go big or go home. I say 1-7/8 on that dude, especially if you want to throw a cam in with the blower. Cam'd and maggie'd LS2 should get you 550rwhp pretty easily, that's about what NineBall makes w/ his 05 C5.

s346k

iTrader: (4)

yeah, definitely go with the 1.875" headers. boosted engines don't need backpressure. your need for larger primaries will increase if you add a cam on top of that already beastly setup.