Call me "McFly".....I currently own a 2007 Mazdaspeed6 in Titanium Grey.
I've done a few cosmetic mods, as well as a Mazdaspeed CAI, HKS SSQV
Blow off valve, and I'm currently contemplating a cat back exhaust.
Been working on cars most of my life, and consider this car 'a work in progress'.
I live on the Space Coast in Florida, where I praise the discovery of freon on
a daily basis.

 

Welcome McFly - I'm in Orlando and praise the AC gods daily myself. Your Speed 6 sounds nice. I just sold an Mx6 V6 with many of the mods you mentioned (no turbo of course). What really opened up the exhaust was the addition of a high-flow catalyst to the Cat-backsystem (kept things legal too). Together with the larger throttle body, underspeed pullys, CAI, and headers, I picked up about 35 hp according to the dyno. Every 30 hp knocks about .7 -1.0 sec. off the 0-60 time so your 6 should be seriously fast when you're through. Keep us posted.