Your thumb is not pressing down on the piston is it, it's the pressure psi from the combustion that is, which has a relatively narrow range of psi based on efficiency not displacement, average car to highly efficient race car 1000-1500 psi a Max effort Pro Stock has 1600-1700 psi.
Here you go, Piston area and force.
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Again were talking combustion psi not lbs of force.
Comparing pressure per surface area of a piston might be useful when looking at relative efficiencies of a design. Similar to the way comparing power per cu. in. is used except in this case focusing on one aspect.
One could also work backwords for certain types of piston applications where the goal is to create enough pressure for the piston develop a force great enough to allow the piston to move.
One could also work backwords for certain types of piston applications where the goal is to create enough pressure for the piston develop a force great enough to allow the piston to move.
Newbomb Turk
Well-Known Member
Well then we can close this thread. If the wife says bigger pistons make more power, who are we to argue with her?
I know I’m not arguing…lol
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Newbomb Turk
Well-Known Member
If you are going to quote a book, you should actually READ the book first and then go back and look at the pictures.
Like people of your type do, you jumped ahead in the book and didn’t READ what he said BEFORE he posted the formula that explains what he’s talking about.
The fact that you continue to do your usual bullshit shows you refuse to learn. Or even admit you are dead wrong.
Your arrogance is appalling. You take things out of context. You make baseless claims and then vomit out a bunch of irrelevant **** that takes 1000 times more work to refute than it does to promote the errror.
Want an example of what clowns like you do? You say “the moon is made of cheese, prove it’s not”.
To refute that with PROOF requires an immense effort and when you are done proving it, the pole cat making the claim still argues the error.
Same for the flat earth types. No proof can move them.
You are THAT guy.
4eighteener
Well-Known Member
The very definition of, ad hominem, and used quite a bit here
Bewy, hint, to prove us wrong, All you have to prove is for same displacement the bigger piston engine generally has less psi and less psi generally by the percentage difference between the piston area. And not by some old science book but actual examples of automotive engineers or text saying it.
In the 383 B vs RB, 4.25" vs 4.03" that would be like 1000 vs 1100 psi which is a fairly big difference especially when a 1000 psi is considered average car and 1500 psi decent race engine and 1600/1700 psi is Pro Stock.
If that was the case any engine class with a cubic inch rule, they would probably run severely under square engines to make 100's of extra psi.
If you can provide real proof of this average psi loss and not some dog turd and a garden hose I'd listen to you, anything short of that you ain't proving anything wrong.
But if it is reasonable that both engines can make similar psi then you are wrong, and if a 1000 psi is considered around what the average passenger car engine makes from a 1l to 7l + no matter there bore and stroke ratios I don't think your gonna find such proof.
In the 383 B vs RB, 4.25" vs 4.03" that would be like 1000 vs 1100 psi which is a fairly big difference especially when a 1000 psi is considered average car and 1500 psi decent race engine and 1600/1700 psi is Pro Stock.
If that was the case any engine class with a cubic inch rule, they would probably run severely under square engines to make 100's of extra psi.
If you can provide real proof of this average psi loss and not some dog turd and a garden hose I'd listen to you, anything short of that you ain't proving anything wrong.
But if it is reasonable that both engines can make similar psi then you are wrong, and if a 1000 psi is considered around what the average passenger car engine makes from a 1l to 7l + no matter there bore and stroke ratios I don't think your gonna find such proof.
jos51700
Green Bearing thread connoisseur
I advise you to take a thermodynamics class and get back to us.
Isn't he the guy that you were taking advice from on port timing awhile back?
I also advise you to walk away. You're not conveying your position well, and even if you were, do you really think that anyone is reading all that?
I post mega-tech posts too, but I don't expect a single sole to read the silly things.
Newbomb Turk
Well-Known Member
Just for posterity who may come along later, here is what Harold Bettes said about piston area. And like Bewy says, he KNOWS what he’s talking about until someone makes claims he never did.
Right out of his book, long before he added the part Bewy posted. You can read it for yourselves.
Sorry it’s going the wrong direction.
Look at what Harold really said.
“In general, power is proportional to piston area”.
Ok, what did he really say? He’s saying that as a general rule, a bigger piston makes more power.
Then to clarify and solidify his point, he next says “Try to REMEMBER that power IS proportional to piston area”
So power IS proportional to piston area. That means a bigger piston, with more area will make more power.
He even went to the effort to say try and remember. Evidently some don’t try and some do try to remember and still don’t.
Others just don’t give a **** if they are wrong, they just put their head down and continue bullsquirting around.
And if it was not proportional he would have said piston area is the INVERSE making power.
That’s not what he says. It’s not what the math says. It’s not what the real world says.
jeff alder
Well-Known Member
What you are saying is pretty much true for all. A simple porta power...bigger cylinder more force. It's all about the math and the physics.
jos51700
Green Bearing thread connoisseur
I'm not arguing the internal combustion merits of the discussion at all. I see some people here using very general guidelines without including any of the additional constraints that really should be included.
There's no replacement for displacement. I don't need to cite a book to prove that.
Well, it wasn't "just" him, but yes. I try to have an open mind about trying new things and this one happened to work.
My wife is usually right, unfortunately she doesn't pull any punches. lol
How can anyone with even half a brain buy that nonsense?
There comes a point of diminishing return
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Bore size is one of the ultimate main limiting factors to hp but for most were not making enough hp to overly worry about it, most aren't even pushing what a 318 bore is capable of and really a 360 bore is less than 3% bigger than a 318 bore and a 340 bore is slightly more than 3% compared to a 318, even a 273 bore should be able to handle 400 or so hp without crazy work. For most bore size ain't a huge issue, making power at an reasonable rpm for that person is probably a more pressing issue for most which usually mean a higher power to cid ratio aka no replacement for displacement.
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Newbomb Turk
Well-Known Member
Yeah, diminishing the pocketbook. lol
Newbomb Turk
Well-Known Member
yea that, but you won't find many 500 ci big blocks competing with a Brett Miller prepped 422 or 440 W8 engine. The gains on the big block have diminished to a point they can't compete
big cubes in particular.
Did your wife tell you that mine did and it wasn't the wallet.
I told you she doesn't pull any punches, but red heads are that way. well she's silverish white now. lol
My guess it's harder ($$$$) to get heads with enough area to spin 500 + cid engines.
If someone would make a W2 style head for the big block, that would level the playing field.
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