Dodge has been pushing the envelope with its muscle cars in recent years, and Challenger R/T with Scat Pack ($38,995) is among the very fastest below $40,000. With an output of 485 horsepower and 475 pound-feet of torque from the 6.4-liter V8 engine and the 392 Hemi Scat Pack upgrade, you will be the king of most highways. Motor Trend hit 60 miles per hour in 4.2 seconds and reached a quarter mile in 12.6 seconds with this model.