Thread: Engine Braking
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Old 10-02-2012, 08:38 AM   #8 (permalink)
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A dyno test I found showed 20HP of power for 1 unit of fuel at 20 HP for a 4 cylinder engine. When the load was increased to 50 HP the fuel consumed only rose by 50% while the power increased by 150%, at the same RPM.

This is because the in cylinder compression was increased from about 50% of atmospheric pressure to 100% of atmospheric pressure. With twice the actual compression and twice as much fuel, the engine produced 1.5 times as much power.

30 more horsepower on half again as much fuel. 50 HP on 1.5 or 2 HP on 1. The higher horsepower divided by the fuel consumption gives you 32.66 HP per unit, compared to 20 HP per unit at the lower load. Using the higher unit per fuel to add inertai to your vehicle means you can average the same speed while using a lot less fuel. The essence of P&G.

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