fuel problem need help
 

when i baught my fc it had a hks programed fuel system computer [piggyback] aswell as the stock computer but i didnt realise the hks wasent pluged in,the harness was installed tho. I had 2 get the engine rebuilt for other reasons but the mechanic could not tune the rebuilt engine with just the stock computer could this b because the stock computer has been remaped or something to suit the hks computer

Ars you refering to the F-CON? you should be able to use it as a piggyback with your stock ECU. The stock computer should not need to be remapped with this piggyback system. IIRC the F-CON uses a different 3 bar map sensor than the stock unit.
Could you be more specific on what your mechanic is not able to tune?

sorry, fuel and air mixture im pretty sure!!, and ur correct [F-CON]