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smokingwheels
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I have an spark ignited 4 cylinder 2000 cc engine in a wagon and I think its 50% thermally efficient at idle due to the mods I have done on the intake manifold.
My engine uses (mesured on video) roughly 9.807 cc/min at approx 750 rpm and the only reference I have come across is a similar engine uses 5kw of fuel just to idle which works out at 29.55 cc/min of fuel.
Is 5kw for idle a good guess?
I have the video of the idle test on youtube, if anybody is interested I will post the links.
so I did the percentage 29.55 - 9.807= 19.743 then (19.743/29.55)*100= 66.8% then assuming an engine is 30% efficent 30*.668= 20.04 then 20.04% +30% = 50.04% is it ok to add the thermal efficency on to the original number?
If not how would I work it out the thermal efficiency at idle?
Another thing my city consumption is 58% better about 7l/100km and my hwy consumption is approx 34% better at approx 7l/100km my engine seems to work better under light loads.
Its very strange to have hwy and city nearly the same that is pushing a law of physics.
Another thing my engines idle increases by 9.33% when the temp goes from 160 deg f to about 200 deg f the above tests where done with a 160 deg thermostat, I now have a 195 deg F thermostat and I will fit it soon and retest my engine to see if I get a 9.33% increase.
My first real test of my engine in 2005 was 340km to approx 14 L of fuel at 80km/h with a 190 or 195 deg F thermostat this is nearly 100% more efficent but it was running very close to knocking most of the way, since then some one has sliped silicon in my engine and damaged it so its not as good as it used to be.
<< link to commercial whereis website removed by berkeman >>
My engine uses (mesured on video) roughly 9.807 cc/min at approx 750 rpm and the only reference I have come across is a similar engine uses 5kw of fuel just to idle which works out at 29.55 cc/min of fuel.
Is 5kw for idle a good guess?
I have the video of the idle test on youtube, if anybody is interested I will post the links.
so I did the percentage 29.55 - 9.807= 19.743 then (19.743/29.55)*100= 66.8% then assuming an engine is 30% efficent 30*.668= 20.04 then 20.04% +30% = 50.04% is it ok to add the thermal efficency on to the original number?
If not how would I work it out the thermal efficiency at idle?
Another thing my city consumption is 58% better about 7l/100km and my hwy consumption is approx 34% better at approx 7l/100km my engine seems to work better under light loads.
Its very strange to have hwy and city nearly the same that is pushing a law of physics.
Another thing my engines idle increases by 9.33% when the temp goes from 160 deg f to about 200 deg f the above tests where done with a 160 deg thermostat, I now have a 195 deg F thermostat and I will fit it soon and retest my engine to see if I get a 9.33% increase.
My first real test of my engine in 2005 was 340km to approx 14 L of fuel at 80km/h with a 190 or 195 deg F thermostat this is nearly 100% more efficent but it was running very close to knocking most of the way, since then some one has sliped silicon in my engine and damaged it so its not as good as it used to be.
<< link to commercial whereis website removed by berkeman >>
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