XGTRX just won the internet! NO BACK PRESSURE IN FORCED INDUCTION! Think about it? How do turbocharged engines produce torque? Yep you guessed it! A turbocharger! The sooner you get it spooling the sooner you start producing more torque! If you create "back pressure" either side of the turbine you introduce lag and lose down low torque. Back pressure in turbocharger talk is something we call "a restriction"