It exists, I have never seen it in a car, but Eastern Aerospace makes a NOS Kit for Turbocharged Volvos
http://www.easternaerospace.com/automotive/engine/
They claim 30-40% hp and torque increases, it is about $600. I personally would also buy the progressive timing kit, sure it costs $495. But hey, if you want NOS, you should get the timer. Also, I heard it would seriously lessen the life of your engine
http://www.easternaerospace.com/automotive/engine/
They claim 30-40% hp and torque increases, it is about $600. I personally would also buy the progressive timing kit, sure it costs $495. But hey, if you want NOS, you should get the timer. Also, I heard it would seriously lessen the life of your engine