i bored out my carb and enlarged the jet and played with the accelerater pump...big difference...u just have to worry most about smoothing out the venturi when u are done making it larger....with the same carb stock i could go to about 80-85 km/h in first before i lose my power..now i can bomb it right to 100km/h full power band...might go higher but thats the peak RPM i'm willing to go...but if u switch to the 2BBl with adapter u may need to get a new gas pedal cable...or just fab something up...also i dont know how the kickdown will be set up, but something will need to be changed there as well


got my 78 merc with a 250 I6 and i love it.