whats the best engine for both performance and mileage??

Turbo 4 bangers are what the factories are now doing, even BMW - for their cheaper wheels

Wll those engines last as long, lol but they gotta last as long as 4 inch stroke SBM engines

I would wait till those engines hit the junk yards, least with these new cars its easier then ever to total the car out. In 3 - 4 years the junk yards should be fill of 2013 turbo 4 cylinders