A HEMI engine has hemispherical-shaped combustion chambers rather than wedge-shaped combustion chambers in the in-line valve setup common in most engines. The hemispherical chambers make it possible for the engine to have larger, straighter valves, which makes for better air flow and improved engine breathing. Altering your driving style and maintaining the engine will improve the fuel economy of the high-performance HEMI.
Fill the HEMI's tires with nitrogen rather than standard air. Nitrogen improves tire pressure retention, which leads to better fuel economy. Nitrogen also lengthens the life of the tire.
Stay up to date on maintenance checks. Car problems, such as sticky calipers and dirty air filters, lead to a decrease in fuel economy. Car maintenance is one of the best ways to improve fuel efficiency in a HEMI.
Use fuel additive to improve handling and fuel economy. Clean with a fuel injector cleaner every two tanks of gas. Use a good brand of fuel additive, such as Shell or Lucas. Replace fuel injectors every 75,000 miles.
Change your driving style to improve fuel economy. A HEMI is a high-performance car, and it is tempting to drive fast. Put the cruise control on when driving on the highway and accelerate slowly from a stop. Every time you slam on the gas, fuel economy decreases. Anticipate stops ahead by letting your foot off the gas and slowly coming to a stop, rather than accelerating and having to slam on the brakes.
