摘要 |
A process and apparatus for improving fuel economy and exhaust emissions of internal combustion engines operating at high altitude conditions. The process is comprised of adjustments to spark timing carburetor idling and crankcase ventilation flow to lean out the fuel-air mixture an amount based on the relative elevation in altitude. The process includes the use or modification of a crankcase ventilation modulating valve having novel flow characteristics and produces much greater efficiency than would be expected under the high altitude conditions. The manifold vacuum between the engine carburetor and piston modulates the valve to provide a greater air flow when increased power is demanded from the engine. In addition to coordinating the spark timing with the modulating valve air flow, the process includes a concomitant special adjustment of the engine's speed and fuel air mixture at idle.
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