Who's 4" kit do you have for exhaust? Are you useing a pipe that is crimped down to the stock 3" at the end? I replaced my stock exhaust elbow with a banks power elbow and it really seemed to help it out. I don't have a comp box on mine but the EZ is always on 3 and I got 80 HP injectors in it. Nother thing would be to ditch the muffy to open the exhaust up as much as possible. You could also try cutting the bottom out of the stock airbox. I did it and dropped about 75 degrees on the pyro