First off.. AWD setup... is supposed to drain a lot more than 15% only... I'm pretty sure 15% is something you'd see on a Front or Rear wheel drive vehicle.....
Granted our AWD setup is only active once the traction control system kicks in...
Anyway... Cat-back exhaust isn't going to show the numbers you want.. for the price you pay... There is a guy somewhere around here who claims to be pullin 300+ hp at the wheels... Or somethin like that... Runs pretty good numbers as well.... like mid - low 13's....
He has an exhaust cut-out which bypasses some of the cats on the vehicle... which is where you gain performance.... gettin rid of those restrictive cats...
Boost guage... is for fun... Boost-controller.... Umm... from what I've read, doesn't work properly with our turbo... I could be wrong about thi.. and I plan on doing more research on this subject soon...
I suggest ordering the Downpipe CPE is offering... you'll see good gains by removing the cats.. and restriction... as well as open up future upgrades like the rest of the exhaust... and ... so on...