- #1
smokingwheels
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The law says that the maximum thermal efficiency of a heat engine can be 88%.
If I have and internal combustion engine using 9.8 cc/min instead of 25 to 30 cc/min and the other accepted figure is a 2L 4 cylinder engine for idle is it uses approx 5 HP of fuel just just to idle.
So I am doing the same work as 5 HP of fuel at 30% efficiency but now only using 2.43 HP worth of fuel.
If my maths are correct a unmodified engine uses 105.76% more fuel.
Its been said my engine efficiency was around 78% is this true?
Could someone please do the numbers for me to see if the 78% is correct?
If by chance I raise the compression ratio of my engine it will become more efficient because the ignition phase pressure build up compressive losses will be reduced eg if I have to start the ignition phase after top dead center.
I currently have an engine that needs the timing to be roughly 4 degrees after top dead center at 500 rpm the other point is at about 1427 rpm it is roughly at top dead center my engine has a timing slope 0.0035 per rpm in a 1 demention graph.
I have video evidence online of the 9.8 cc/min if anybody would like to see to confirm my results.
If I have and internal combustion engine using 9.8 cc/min instead of 25 to 30 cc/min and the other accepted figure is a 2L 4 cylinder engine for idle is it uses approx 5 HP of fuel just just to idle.
So I am doing the same work as 5 HP of fuel at 30% efficiency but now only using 2.43 HP worth of fuel.
If my maths are correct a unmodified engine uses 105.76% more fuel.
Its been said my engine efficiency was around 78% is this true?
Could someone please do the numbers for me to see if the 78% is correct?
If by chance I raise the compression ratio of my engine it will become more efficient because the ignition phase pressure build up compressive losses will be reduced eg if I have to start the ignition phase after top dead center.
I currently have an engine that needs the timing to be roughly 4 degrees after top dead center at 500 rpm the other point is at about 1427 rpm it is roughly at top dead center my engine has a timing slope 0.0035 per rpm in a 1 demention graph.
I have video evidence online of the 9.8 cc/min if anybody would like to see to confirm my results.
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