proven technology
needs and criteria of a B + heavy duty engine market
fuel economy
cost versus benefit prediction
integration possibilities in industry fabrication standards
reduced emissions

Sleeve Valve Engines (similar technology in terms of piston lubrication) were built in very large numbers and used successfully in WWII warplanes. While SVE's demonstrated 10 times lower cylinder wear rate and established records for fuel efficiency, they would not meet today's stringent emission standards. The RLE exploits the design characteristic of the SVE that lead to reduction of wear and friction, in a way that will meet those standards. The SVE/RLE characteristic, (interaction of a rotating liner and reciprocating piston reduces both friction and wear), is optimized for
friction reduction, resulting in higher friction benefits
than the SVE.