Alright very fair point everyone has been getting a bit ahead of themselves, me included Have you got a tuner ? Have you asked them what they want installed/modified to get you to 350-400kw We all can recommend what we like but it comes down to the tuners knowledge/preference You might put piston brand "A" in your engine and the tuner might not like pushing them to a certain point or has had a bad Experince with them. He might prefer brand "B" cause he has had no problems with them This applies to all the parts really, so you gotta speak with the tuner, or multiple tuners and get quotes And I was only using the Pistons as an example