so the same tuner that tunes it originally said his own tune was to lean and had too much timing in it or did you touch anything since it was last tuned? if its the same tuner then id find a new tuner to go to....as far as motors are concerned i wouldnt bother having one built....simple solution is get the ford racing 347 or 363 cubic inch shortblock put your too end on it and call it a day...then put it on a trailer and head down to lidio at alrernative auto in michigan for the tune...again just my opinion. hope it works out. cheers!