Bad mpg?

[blanchard7684]

You do realize that if you put the same quantity of air in two different volume cylinders, the pressures will be different right?

For a given set amount of air ,,,, say that amount of air needed to perfectly burn a given amount of fuel at stoichiometric ratio, if you put that amount of air in a smaller engine then;

View attachment 447886


But if you take that same amount of air (the amount needed to burn a given amount of fuel at stochiometric), and put it in a larger engine, then you get;

View attachment 447887

Maybe I should have mentioned this earlier, but I just kinda assumed this was a common sense thing.

So burning the same amount of fuel, at the same afr (which requires the same amount of air) in two different displacements engines makes the same power ( assuming the engine efficiencies are the same of course).

That lecture you keep referring to even alludes to that later on when talking about ways to raise power, see Pressure (adding boost) at BDC statement below.

View attachment 447891

I think that maybe you've not be seeing the forest for the trees and focusing on just the equation as symbols, and not what the equation is actually doing/ telling you. Which happens even in the adult / professional world every now and then.
...

Here is the quote you want. Post 167.

This example literally says that by Boyle's law, lower displacement raises Pbdc which can make same power as a higher displacement with lower Pbdc-- if everything else is the same.

So if I increase Pbdc, by reducing displacement, I get more power. This is justified by Boyle's law. So if I keep reducing displacement, I keep getting more power.

I'm not walking through this absurdity again.

This is why I'm mocking you.

You have beclowned yourself.

I'm seeing if I can model a cylinder in a program that is 0.25" to see what kind of insane power I get.

 

[Marky Dissod]

You guys have had a somewhat rambling but very interesting discussion in this thread. I've learned a few things reading it. That's the good.

The bad is that you both acted like spoiled children throughout the discussion, insulting each other in numerous ways, something I'd expect on Facebook or X (though I read neither), and not something that all of the rest of the adults on this great Forum care for or want to be part of.
And, personally, I don't care which of you is right or wrong in the discussion.

@Fless @soulsea
IMO, this thread should be closed, as this is not the type of respectful adult interaction that we want (newbies to see and replicate) on this Forum.

I definitely care who is right and who is wrong - and it's not an interesting 'discussion'.
Only one properly provided all the 'very interesting' and technically factual info, that you (and others) learned from.
There is no meaningful justice in painting them both with the same brush.

Hopefully the admin bother to tell the difference between the two.

 

[blanchard7684]

AntonM You have an irredeemable knowledge gap here.

There is no sensible reason to continue discussing a technical matter with someone who 1) has a clinical grade personality defect 2) is concocting preposterous technical statements and 3) quintuples down on both 1 and 2 and 4) is a miserable and resentful person whose life didn't turn out the way they envisioned, 5) didn't take any combustion classes when he was busy getting C minus average in his supposed engineering degree.

Sorry to burst your overinflated ego, but you are a clown.

Have fun with your gas laws.

BTW my engine program said a 0.25" cylinder only makes about 1 hp under ideal conditions.

Clearly this is in error. It should be at least 12 hp since Boyle's law says so. I'm sending a note to the company to fix this.

 

[blanchard7684]

lol , this is the engineer that everyone that calls themselves an engineer really is. Just like people that call themselves alpha or whatever other dumb shit they think makes them seem impressive to others. If you gotta tell people that you're something, then you aren't whatever that is.

View attachment 447974
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So engineer then?

Got it.

 

[Antonm]

Are you thinking

Here is the quote you want. Post 167.

This example literally says that by Boyle's law, lower displacement raises Pbdc which can make same power as a higher displacement with lower Pbdc-- if everything else is the same.

So if I increase Pbdc, by reducing displacement, I get more power. This is justified by Boyle's law. So if I keep reducing displacement, I keep getting more power.

I'm not walking through this absurdity again.

This is why I'm mocking you.

You have beclowned yourself.

I'm seeing if I can model a cylinder in a program that is 0.25" to see what kind of insane power I get.

Ahhh, lets look at post #167 then, and dive right into how you are misinterpreting/ twisting 9th grade level math , trying your hardest to make it say something that it doesn't, shall we.


Look at the second line of that post (post 167) ,,what does it say,,, it says "For a given set amount of air ,,,, say that amount of air needed to perfectly burn a given amount of fuel at stoichiometric ratio, if you put that amount of air in a smaller engine then;"
Maybe you missed the "given amount of air " part because it wasn't conducive to your crazy, or because of your reading comprehension issue.

The quote of mine from post 167 above is 100% true, and it always will be. Not sure why you're having hard time with this.

Remember, we were discussing the topic of two different engines (a 5.3 and a 6.2) both operating at the same power level during part throttle cruising. So that amount of air that is trapped, is the amount of air needed to burn a specified amount of fuel at stochiometric ratio.

This is the air trapped in the cylinder before compression (which is also before combustion, and I think you're confusing pressure at bottom dead center with combustion pressure).

If you take this set amount of air and stuff put it in a smaller cylinder, pressure will in fact go up. But what does that do to power, lets see (again using your own equations).



Oh that's right, nothing, because its the same amount of air that was needed to burn that given amount of fuel.

Its almost like I've mentioned that power comes from fuel before, and the power you make is depended only on the engines efficiencies and the amount of fuel it can burn,,,oh wait, that because i have said that before, even used your own equations to show that, but lets show those equations again because apparently you forgot.



and just in case you also forgot what all the non-boxed terms that aren't in both the fuel flowrate and power equations are then here you go,,, its efficiencies and fuel heating term.



So no where did i say that changing displacements changes power (in either direction, up or down), I've always said what is true, and that power is dependent on the engines efficiencies and how much fuel it can burn.

And to burn a given amount of fuel, which would equate to a given amount of power, you need a given amount of air, and if you change the cylinder volume that amount of air is in, then the pressure will most definitely change, but since its the same mas of air, just at a different pressure, it'll still burn the same amount of fuel/ make the same power.

If you want to make more power, the you need to trap more air (so you can burn more fuel).

So if you would like to jump subjects from two engine of different displacements that are making the same power at part throttle cruising (which has been the topic we were discussing) to the topic of full/ max power race stuff,,,I'm good with it. I've been a hot roder for decades, making more power is the fun part, one just has to understand the basics (which you are struggling with) in order to get that fun part.
...

 

[Antonm]

AntonM You have an irredeemable knowledge gap here.

There is no sensible reason to continue discussing a technical matter with someone who 1) has a clinical grade personality defect 2) is concocting preposterous technical statements and 3) quintuples down on both 1 and 2 and 4) is a miserable and resentful person whose life didn't turn out the way they envisioned, 5) didn't take any combustion classes when he was busy getting C minus average in his supposed engineering degree.

Sorry to burst your overinflated ego, but you are a clown.

Have fun with your gas laws.

BTW my engine program said a 0.25" cylinder only makes about 1 hp under ideal conditions.

Clearly this is in error. It should be at least 12 hp since Boyle's law says so. I'm sending a note to the company to fix this.

The random blathering of an idiot that has no idea what he's taking about,, and this why I call you "clueless guy"

I've shown you , multiple time, using your own equations, just how wrong and silly your are (btw, silly is another nice word for dumb).

So you go off on how Boyles law is wrong (you'd think that before they called something a law, that it would be proven true, but I guess you know better that all the silly scientists over the past 400-ish year combined do).

You started off as a clueless troll saying nonsense, and its only gotten worse. At this point its either willful ignorance/ denial that you were wrong, or you seriously have some issues with basic math and comprehension.
...

 

[Antonm]

So engineer then?

Got it.

Yes actually, for almost three decades now (man I'm getting old), but if the new guys coming out of school are as dumb as you are, at least I've got job security. So I guess I should be thankful to you for that.
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[blanchard7684]

AntonM’s law: where smaller engines make same power as larger engines, because pressure goes up at bdc.

 

[B-train]

I'll bet the OP regrets posting this thread.

I'm almost regretting reading it.......

It appears there was something lost in translation that has become a pea under a mattress.

 

[blanchard7684]

Next up: Charles law. Overheat your engine so, it's displacement goes up!