A stock Gen V will make about 20hp more than even the best ported Gen lll on a modded set up. Many things make the Gen V better, larger and straighter intake side. The rotor coating is a big factor creating a much better seal and increasing efficiency. The outlet is farther forward allowing the air to exit the blower much easier. The blower case is machined to fit all the way around the rotors where the Gen lll leaves a gap of free space at the bottom center. You will GAIN boost over the Gen lll even if you run the same size pulley.
