CAFE standards don't work how you think they work - they require a fleet average of 54.5MPG by 2025. Fleet average doesn't simply have you average out every car in a company's profile - it actually takes into effect the amount of cars each model sells. Sports cars and muscle cars will only get more powerful because they do not account for a large portion of a manufacturer's sales. Of the 2-Million cars a company like Ford sold in 2011...only about 40-50k of those were Mustang 5.0s - a mere 2.2%. Plus, the amount of technology that exists makes 54.5MPG a very achievable goal in 13 years.
This is why US car makes are hauling out more and more small cars from their European markets with smaller motors - they hope they drive enough sales to boost their fleet numbers up. And also why Daimler officially added Smart to their profile of US cars, again, just a quick and easy tactic to raise their CAFE average MPG across the entire range of vehicles. Car companies lobbied the government to change how CAFE works, which allowed the practice to base it on the sales of a certain model, as opposed to averaging out the overall company's MPG - so companies with a wide array of high-selling fuel efficient cars such as Ford, GM, Nissan, etc. can easily release super powerful cars because they are low volume sellers.
Petrolheads, worry not.
