Does anyone know what the difference was between the Rochester E4ME and the E4MC used on the 86 Trans Am, and possibly other years? Thanks.

 

AFAIK there was no E4MC used on any of these cars, they are all E4ME. E = electronic, 4M = the carb model (4M is teh model # of the Q-Jet), E = electric choke. C = integral exhaust-heated choke, these cars did not come with that.