The new 3.7L Ti-VCT V6 engine in the 2011 Ford Mustang is the most powerful production V6 ever in a Mustang. And it offers up to 31 miles per gallon highway, making it the most fuel efficient in its class.*br br br *EPA-estimated 19 city31hwy23 combined mpg. Coupe, available automatic transmission. Class is Sports Cars vs. 2010 competitors.br br br img src="" alt="2011 Ford Mustang: New 3.7L Ti-VCT V6 Engine" title="2011 Ford Mustang: New 3.7L Ti-VCT V6 Engine" width="150" height="90" alt="2011 Ford Mustang: New 3.