|The pintle-regulated venturi concept. Click to enlarge.|
Independent testing of PRV Performance’s Pintle-Regulated Venturi Induction prototype car (a Honda Civic, earlier post) delivered 48.1 mpg in the EPA highway test. Carbon dioxide emissions were 106 g/km. Testing was performed at Environmental Testing Corporation in Aurora, Colorado.
The company has worked through eight generations of prototype, installed and tested in a Honda Civic with a JDM D15B single overhead cam engine. (The JDM D15B was a 1.5-liter SOHC engine applied in the MY 1992-1995 Civics.) EPA fuel economy ratings for the 1995 1.5-liter Civic ranged from 33-41 mpg. EPA highway fuel economy rating for a current, conventional 1.8L 2008 Honda Civic with five-speed automatic is 36 mpg.
PRV induction, with fuel injection directly at a variable Venturi throat, effectively mixes fuel and air due to the high velocity and reduced pressure at the vapor-liquid contact region. Pressure is recovered in the expansion section of the Venturi, thereby reducing engine pumping losses. Fuel vaporization and homogeneous mixing with air improves the burn rate in the cylinder, delivering more complete combustion early in the ignition cycle to improve fuel efficiency.
Road tests of a Honda Civic revamped with a pintle-regulated Venturi fuel induction system demonstrate a 25% increase in highway fuel economy, a 14% increase in city fuel economy and a 15% increase in torque across the entire rpm range, according to the company.
The company will present a paper on the PRV system and the test results at the SAE World Congress in 2008.