Hi,

Did you have the conversion done, or was it on the car when you bought it, dont you mean stage 3, ie 803's green injectors, uprated actuator 3,bar map sensor, etc.

If it is as you say running lean, you dont want anymore air?,
What boost are you running, as stage 3, runs approx 25 peak and solid 22/23psi, depending on tuner,

If it is a MSD chip, give stu a ring and he will tell you what boost, fuel pressure etc the car should be running, also the pump should of been uprated( escort cosworth) when the conversion was done or the engine will run lean,

Regards Dave R.