Think this is one thing i should of done was research if power increase makes any difference to the ST170 and what really works before spending my hard earned cash on it.. as the Scorpion exhaust cost £270 plus fitting £320, bluefin £227, managor leads £50, denso spark plugs £48 and Pipercross foam induction cone filter £65.. the spending of £710 on its mod's and feel i'm possibly going mod crazy to improve its power but not with real powerful result.. just love the car but feel it should be giving true power that it's not which has been my addiction.. will look into the cost of my local tuner ap motors or alan jeffery to get it diagnosed if my bluefin's diagnostics option is not equipped for this job..