On a TD04, are there like rough guidelines to how much BHP it makes at given boost (bar)? Also should i change my headgasket before putting TD04 on as a safety precaution. I'm nearly on 200k with a fair bit of it measure in miles. My engine is on stock internals, at the moment i'm running 1.0 Bar on CT9. Will my engine handle 1.0 bar with TD04 and how much power roughly with 1.0 bar on stock engine will i make. I have fueling mods, RRFPR, FCD obviously, HKS AFR adjuster, Walbro 255lph thats about the fueling mods i can think off. I'm sure its on stock injectors. Any other help welcome for a first time install.