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Old 04-05-2014, 07:01 PM   #3 (permalink)
pgfpro
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The data came from ECM Tunning data logs from last year.
The 3000rpm log.


The 2350rpm log.


I then put the data into a EFI University engine simulator.
The graph that I'm showing is one I made by just putting that info into a spreadsheet for visualization purposes.
I like to visualize things, in this case it helps me put it into perspective of how much the engine is feeling the pumping losses per-second.

The 2350rpm sample shows the reason why I needed more fuel to over come pumping losses and the outcome of this is a poorer BSFC number.
25 intake strokes a second making a vacuum of -9.36 inch/hg the engine has to over come. Also a lower air pressure at the intake valves of only 68kpa.
The lower 68kpa air pressure is not as great at atomizing the fuel verses the 2350 rpm air pressure of 95kpa.

The 1200rpm graph showed me that there is a lot of time after the cylinder would fill and equalize cylinder pressure and start reversion.

Anyway I hope this will give some people on here some ideas, and if anything maybe we can have some great discussions.

To answer your question on octane? I'm was running 91 octane when these logs were made. I should of noted that? lol I'm sure if I were to run a higher octane it would result in a better MBT but this is the highest pump octane we have in our area.
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Last edited by pgfpro; 04-05-2014 at 07:11 PM..
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