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Originally Posted by MetroMPG
Here's a question: it looks like the calcs are based solely on top gear, correct?
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In devising the spreadsheet, I assume that you can hit BSFC(minimum) if you are below the speed at which you will hit BSFC(minimum) in top gear. You have 4 gears to do this with, so it's not a bad assumption. It'll be near enough.
Above that speed, the BSFC is the best you can do for that rpm in top gear.
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The major difference was that I was pulsing in 2nd and 3rd gears, not 5th.
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As explained above, it should work at all reasonable speeds you'd pulse and glide with, assuming you accelerate at 62% of BMEP available at that rpm, that you choose the gear that will enable you to get closest to BSFC(minimum), and that the glide speed drop is not too large (it uses air resistance calculated at the average speed, so if you give it a pulse to take you up to a high speed, most of that energy is wasted in pushing wind). It also assumes that most cars don't deviate much from these maps.
You can't achieve peak FE without P&G, and current instantaneous FE meters will not teach you how to P&G properly. Instead, you learn to accelerate anemically in all circumstances.
That's where this spreadsheet comes in - you can fiddle with variables and see what is theoretically achievable with your car, before you spend money and time on building something, and also how you will have to drive to get those benefits. Then you go do it, and confirm it.
I thought so, just needed some people to play with it. It appears to be in the ballpark for my car, but I wanted some confirmation. Thanks for providing some! It's gratifying that it appears to be working so well. Provided I've got the equations right, it should work. Newtonian mechanics works just dandy at those speeds, and all we are doing is calculating fuel used in a pulse, fuel used in a glide, and the distances traveled in each to come up with a distance/fuel figure.
After that, we are relying on the particular engine maps (which were an average of several manufacturers' cars) being applicable to our cars, my assumptions as listed in the first paragraph, and that my line of best fit is good. I double checked things as I went.
I'd love to get ahold of all the coordinates of the original engine maps, then I could have it instantly calculate steady state FE for a comparison. One thing at a time.