Ways to Increase Fuel Mileage on a 4.3L Vortec

by Don Kress

The Chevrolet 4.3 V-6 engine used in a number of trucks and vans throughout the 1980s and 1990s. Among the larger V-6 engines produced, the fuel economy often suffered in exchange for impressive torque and horsepower. Making these engines more efficient is simply a matter of adding a few bolt-on accessories, though it is unrealistic to expect the fuel economy of four-cylinder engines or hybrids.

Air Intake Upgrade

The first and most obvious way to improve the fuel economy of your 4.3 V-6 engine is by improving the quality of the air that the engine consumes. This can be done by adding one of two products, both widely available at any local auto parts store. The first is a simple high-flow air filter, which installs in place of the stock paper filter; the second is the replacement of the entire intake track with a cold-air induction kit. Both improve fuel economy, though the cold-air induction kit does so significantly more than the basic high-flow air filter, as is reflected in the price disparity between the two parts. Expect to pay upward of $300 for a cold air induction kit, and less than $50 for a high-flow air filter (as of 2011).

Exhaust Upgrade

The installation of a catalytic converter-back exhaust system works best when installed in tandem with a cold air induction kit. By limiting the restriction of air within the engine, the engine is made more efficient. As a by-product, you will also notice a significant improvement in the throttle response and power of the truck or van. Under normal driving conditions, the additional 20 or so horsepower gained with the modification will translate into at least 1 to 2 additional mpg in fuel economy.

Throttle Body Spacers

Throttle body spacers, when used by themselves, have a negligible effect on the power and fuel economy of the 4.3L engine. However, when used in conjunction with modifications, can significantly improve fuel economy. They do this by increasing the volume of air taken into the intake manifold, as well as spinning the air to help further atomize the fuel-air mixture. The throttle body spacer by itself may only add 1/4 to 1/2 mpg in fuel economy, but used with the exhaust and air intake upgrade, can improve fuel economy by as much as 1 to 2 mpg, in addition to gains realized by the intake and exhaust upgrade.

Computer Programmers

Engine management computers are designed to work with a broad range of variables. Taken into account is the lowest possible octane rating of fuel available nationwide, which is generally 87 octane, as well as a broad spectrum of air densities to account for the different elevations in which the vehicle is likely to be operated. Using a computer programmer allows you to fine-tune the engine of the vehicle to the exact specifications of the area in which the truck or van is usually driven, as well as your preferred octane fuel. Using a computer programmer can increase fuel efficiency by 2 to 4 mpg, depending on driving conditions and your driving habits.


About the Author

Don Kress began writing professionally in 2006, specializing in automotive technology for various websites. An Automotive Service Excellence (ASE) certified technician since 2003, he has worked as a painter and currently owns his own automotive service business in Georgia. Kress attended the University of Akron, Ohio, earning an associate degree in business management in 2000.

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