No worrys bud.. Set the fpr at 3BAR on idle, some people tune them with the inlet manifold vacum pipe on, some tune it with it off. I set mine up with the vacum pipe attatched. Basically, Its allways better to run slightly rich on a turbo, When the turbo boosts up, it basically uses alot more fuel so it will lower the pressure, it will be rich under normal throttle for example, but as soon as the turbo starts boosting up, it will use slightly more. As Sicaln said, Rich is over fuelling, Lean is under fuelling.. Youre more prone to damaging engine internals if youre underfuelling (Running lean) As that will help create Detonation... You should be able to hear the engine "detting" It would make a very light, almost tinny knocking noise. If you run MEGA rich, it will start a process called Borewash. Basically the fuel isnt being burnt off and damages the bores... Youre highly unlikely to ever have borewash, As you need to be chucking UBER fuel into the engine. Detonation is the main thing to watch out for with these , if your running standard engine internals and youre raising the boost levels past the Fuel cut level. Thats all simplified, You can go on a site such as wikipedia to look up the terms more indepth, Borewash & Detonation etc... I have been running my hybrid ct9 turbo, with the standard ECU under fuelcut level (0.8BAR boost) for over 4 months, I have only just got around to buying a piggyback ecu to sort my fuelling out properly. All that time ive been running 3BAR fuel pressure just fine. An easy way to keep an eye on air/fuel ratio levels is to invest in a "wideband" kit. Most consist of a gauge/led display box / Wideband Lambda Sensor which goes into your exhaust system, after your turbo & all the wiring needed.If you fit one of them, it will help you keep an eye on if its running too lean, rich etc. Also great if you plan on fitting an ecu and tuning it yourself. Hope some of that helps bud