To my understanding, reducing exhaust back pressure without increasing air/fuel intake, rewards you with more noise and a reduction in available torque. If you add fuel delivery without the air to burn it, what exactly have you accomplished? A really smelly exhaust, perhaps? An easy fix is to correctly drill/modify your airbox, then you can run 132- 140 jets, restore some balance in the air/fuel/open-exhaust equation and get some of the latent power available.
