Thought this may be handy for those not running pure gasoline.
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Thought this may be handy for those not running pure gasoline.
Good stuff. E15 should be on list, it's coming soon, may be here already in some locations. But its numbers aren't hard to figure out knowing E10 and E20.
Something is obviously wrong with that chart. E20 and E30 are the same.
Whoops.
The other thing is that the WOT AFR ratios are just an estimate, recommendation, or guideline. That will vary with the combination. And you may make more power leaner than that, question is how long can you run that lean at WOT.
In another 10-20 years, we'll discuss all this in terms of lamba, instead of the actual AFR. Flipping it around, because it will be much more common to use a wideband, and lambda is what it actually measures.
I really wonder how accurate or applicable that chart is. Seeing errors like that really makes one question the whole thing imo.
Going back to a prior debate, stoichiometric combustion produces the most power, period. Once all the oxygen is consumed you can't burn any more fuel.....that's a physical fact. The reason you enrichen the mixture under power is to help ensure that you get a full stoichiometric burn and to provide some cooling under high power operation to decrease the occurrence of detonation. The additional fuel used for cooling produces ZERO power. At an ideal 14.7 to 1 A/F ratio the probability that every gas molecule finds an oxygen molecule (or vice versa) in a couple of milliseconds is not 100%, therefore you don't get a stoichiometric burn. By adding some more fuel you increase the probability of every oxygen molecule "finding" a fuel molecule and being consumed in combustion.
That IMO explains why you add more fuel under power. But a theoretical stoichiometric BURN ratio determines the maximum power (heat energy) you can get for a given mass or volume of air.
Here is another one from Hot Rod magazine. I'll bet he's pouring water and not fuel! I just noticed it's missing a few divider lines, something with my screen capture program since the original has the lines there. Of course by now it's common knowledge that a lambda of 1 is not maximum power, as racers have known for some time now.