Is More Flow Better, Is The Smallest Intake Port That Flows The Most The Best

273

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Here's a metric dyno run notice how the torque lines at the bottom are less helpful to know what's going on under the curve. The torque is basically a flat line that curves down as the engine makes more power that's not how it feels in the car, how's does that show the possible rate of acceleration? it's just easier to look at kw power curves that represents how the car will actually acceleration.

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Aussie Charger

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HP, RPM and gearing get the car moving.

Put the gearbox in high gear and see how well TQ moves the car.

There is a reason why torque converter stall speed is usually above peak TQ. Or why clutch guys chip the RPM higher to make the car leave harder.

As long as the tire can take the hit. I have video of several cars pounding the tire to death, but I’m not going to post them because I never asked the guys with the cars if I can use the video.

Its eye opening.
Unfortunately, that's wrong.

To move an object, you need a force.

Horsepower is not a force – it is a measure of work or power. Power is energy transfer over time.

Apply enough torque and you can move any car with any gearbox with any final drive.

Apply a smaller amount of torque and use a force multiplier – ie: gearing (or leverage) – and you can move the same car, but it will take longer to do it. The reason is because you need time to multiply the force.

F = M/A

Force = Mass x Acceleration

The force (torque) accelerates the mass (car). But the car has rolling resistance due to friction and wind resistance. So you must apply the force continually to accelerate the car against that resistance.

Horsepower is the measure of the number of times that force is applied to accelerate the car to overcome the other the forces (friction, wind etc).

I understand what you are trying to say, but the way you are saying it is not, strictly, correct.

Their entire lives they have been told that TQ moves the car. It doesn’t.
In physics terms, TQ most certainly does move the car. Gearing and RPM determine how (gearing), and how often (RPM) that TQ is applied.

The spanner in the works, as I mentioned above, is that in an internal combustion engine TQ is not produced in a linear fashion, and so RPM can also determine where the engine makes the most TQ to be advantageous in relation to gearing and mass (weight). But again, it is not the RPM that determines this, it is only a measure of the point at which it happens (for other reasons).
 

Rat Bastid

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Unfortunately, that's wrong.

To move an object, you need a force.

Horsepower is not a force – it is a measure of work or power. Power is energy transfer over time.

Apply enough torque and you can move any car with any gearbox with any final drive.

Apply a smaller amount of torque and use a force multiplier – ie: gearing (or leverage) – and you can move the same car, but it will take longer to do it. The reason is because you need time to multiply the force.

F = M/A

Force = Mass x Acceleration

The force (torque) accelerates the mass (car). But the car has rolling resistance due to friction and wind resistance. So you must apply the force continually to accelerate the car against that resistance.

Horsepower is the measure of the number of times that force is applied to accelerate the car to overcome the other the forces (friction, wind etc).

I understand what you are trying to say, but the way you are saying it is not, strictly, correct.


In physics terms, TQ most certainly does move the car. Gearing and RPM determine how (gearing), and how often (RPM) that TQ is applied.

The spanner in the works, as I mentioned above, is that in an internal combustion engine TQ is not produced in a linear fashion, and so RPM can also determine where the engine makes the most TQ to be advantageous in relation to gearing and mass (weight). But again, it is not the RPM that determines this, it is only a measure of the point at which it happens (for other reasons).


Another wanker rides the bus.
 

Aussie Charger

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Movement is work, movement happens through time, a measure of movement through time is power in our case hp.
I edited my first comment as I was rude. But it was not specifically directed at you, apart from the bit about Watts (power) being the product of Voltage (potential difference) x Amps (current), as you seemed to be dismissing the voltage part of the equation.

In your example, voltage can be considered TQ (it is the amount of potential flow of electrons) while current is RPM (the rate at which electrons actually flow). Together, they form power (kiloWatts, which can be converted to horsepower).

With enough torque and gearing, you can accelerate a car at a very high rate. The problem with combustion engines compared to electric engines is that, as your RPM increases, the amount of toque the engine produces changes. So gearing is not just a function of TQ x RPM = HP. That is why gearing must also reflect the torque curve of the engine. Electric engines don't have this consideration as they produce the same amount of toque regardless of RPM (internal frictional losses aside).
 

273

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Horsepower is not a force – it is a measure of work or power. Power is energy transfer over time.
Driving car is work, driving is distance over time which is mph doesn't matter if micro fraction of a mile, 0.0000000000001 mph still distance over time any movement has a time component.
 

273

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With enough torque and gearing, you can accelerate a car at a very high rate.
Acceleration is work over time, driving down the street is work over time, moving a fraction of a mm is work over time, hp is work over time and what's hp tq and rpm.
The problem with combustion engines compared to electric engines is that, as your RPM increases, the amount of toque the engine produces changes. So gearing is not just a function of TQ x RPM = HP. That is why gearing must also reflect the torque curve of the engine. Electric engines don't have this consideration as they produce the same amount of toque regardless of RPM (internal frictional losses aside).
Gearing is to put you at the engine rpm at the hp that's needed to do the work. Why people like diesel for work vehicles is peak hp is at very low rpms at operation speed like road speed for trucks your basically able to use peak hp anytime you want, with most gas engines your gonna have down shift and drive down the road at 4000+ rpm to access peak power. In a drag car you gear to so you spend your time between stall to shift points. Rock crawler gear yo spin around peak hp at walking speeds etc...
 

Aussie Charger

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Driving car is work, driving is distance over time which is mph doesn't matter if micro fraction of a mile, 0.0000000000001 mph still distance over time any movement has a time component.
So which comes first: the force (TQ) or the application of that TQ over time (rpm)?
 

Aussie Charger

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Gearing is to put you at the engine rpm at the hp that's needed to do the work.
Gearing puts the engine at the point of most TORQUE – horsepower is simply a measure of how much TQ is being produced at a certain RPM. Gearing takes advantage of the torque curve. Moving the torque curve higher simply means you can apply the same (or greater, or even less) amount of force at a faster rate = more work (horsepower).

Horsepower is a function of torque – not the other way around.

I know we all understand this (except for one obtuse gentleman), so I think we're just talking at cross purposes now.
 

273

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So which comes first: the force (TQ) or the application of that TQ over time (rpm)?
They both happen at the same time it's a running engine always makes both so it's always making power, you have to give an engine a job to measure tq in a dyno but your akso measuring rpm, power.

Look at it this way take an engine less car with a one foot bar fixed to the front of the 4 gear and hang a 500 lb weight off it now you got 500 lbs-ft going to the driveline, it ain't gonna do much even if it moves the car an inch by the weight moving towards the ground it's using up it's potential energy, power.
 

Aussie Charger

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They both happen at the same time it's a running engine always makes both so it's always making power, you have to give an engine a job to measure tq in a dyno but your akso measuring rpm, power.

Look at it this way take an engine less car with a one foot bar fixed to the front of the 4 gear and hang a 500 lb weight off it now you got 500 lbs-ft going to the driveline, it ain't gonna do much even if it moves the car an inch by the weight moving towards the ground it's using up it's potential energy, power.
The 500lb weight is accelerating at the speed of gravity, 9.8ms2. It will accelerate the car at the same rate divided by the mass of the car.

If you know all the variables, you can calculate how much torque an engine can produce without putting it on a dyno. The reason we put engines on dynos to measure torque is because we don't know all the variables.
 

273

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Gearing puts the engine at the point of most TORQUE
Optimal gearing for max acceleration would be variable gearing to keep engine at peak hp
– horsepower is simply a measure of how much TQ is being produced at a certain RPM.
kind of the torque is what one revolution is, hp is the sum of all the revolutions, or to say it another way hp is the sum of all the power strokes per minute
Horsepower is a function of torque – not the other way around.
tq & rpm, torque and rpm move and accelerate etc.. Your car and we call that hp
 

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Post #43. More BS......and from the usual suspect: 'Torque moves the car. It doesn't'.

If there was NO torque, the car would not move.
 

273

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The 500lb weight is accelerating at the speed of gravity, 9.8ms2. It will accelerate the car at the same rate divided by the mass of the car.
Point was tq by itself ain't gonna do anything but hang there.
If you know all the variables, you can calculate how much torque an engine can produce without putting it on a dyno. The reason we put engines on dynos to measure torque is because we don't know all the variables.
If you know any two you calculate the other one
 

Aussie Charger

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Torque is a force.

That force is provided through the transfer of energy.

If we know what the potential transfer of energy is, we can know the force that will be applied.

Potential force – just like voltage – can be measured without application. That means you can measure it without time (apart from the time it takes to calculate! But that's not part of the equation).

For example:

If we know what BSFC (Brake-Specific Fuel Consumption) is for a particular engine, then we can measure exactly how much power it can make for any amount of fuel (all things being equal – I'm not talking about how BSFC changes with engine dynamics).

The fuel is our potential energy (along with oxygen in the air). It contains the potential chemical reaction that can transfer energy from one place to another to apply a force.

If we know what the potential energy is, then we can know what the potential force is. Again, time does not enter into the equation.

Does that now make sense?
 

273

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Torque is a force.

That force is provided through the transfer of energy.

If we know what the potential transfer of energy is, we can know the force that will be applied.
Yes potential, but we start using that potential it is now power
Potential force – just like voltage – can be measured without application. That means you can measure it without time (apart from the time it takes to calculate! But that's not part of the equation).
How much tq does a non running engine make?
For example:

If we know what BSFC (Brake-Specific Fuel Consumption) is for a particular engine, then we can measure exactly how much power it can make for any amount of fuel (all things being equal – I'm not talking about how BSFC changes with engine dynamics).

The fuel is our potential energy (along with oxygen in the air). It contains the potential chemical reaction that can transfer energy from one place to another to apply a force.

If we know what the potential energy is, then we can know what the potential force is. Again, time does not enter into the equation.

Does that now make sense?
Again once that potential is being used were talking power.
 

dirty white boy

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my peterbilt has a 400 hp cummins in it, take couple miles to reach a 100 mph at 80,000 lbs at 2300rpm, my duster makes 400 hp and takes a 1/4 mile to reach a 100 mph at 3200 lbs at 7500 rpm! whats the difference? duster got 400ish ft lbs with 4 gears of multiplication , pete got 2200 ft lbs and 13 gears of multiplication,... now tell me,..whats doing work and whats making it move?? basic 9th grade physical science!! and we got 2 threads now arguing over it, wth??
 

Aussie Charger

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Optimal gearing for max acceleration would be variable gearing to keep engine at peak hp

kind of the torque is what one revolution is, hp is the sum of all the revolutions, or to say it another way hp is the sum of all the power strokes per minute

tq & rpm, torque and rpm move and accelerate etc.. Your car and we call that hp
Dude, you really are trying to confuse matters. It doesn't have to be this hard.

Optimal gearing for an electric engine with a linear torque curve is what?

Can a single piston two-stroke engine produce torque over one revolution? Yes

Can a single piston four-stroke engine produce torque over one revolution? Er . . . Which revolution? The power stroke or the exhaust stroke?

See the problem with your analogy?

The torque is NOT what one revolution is. The torque is generated by the chemical reaction that produces a rotational force (the definition of torque). The torque/force/potential energy already exists in another state (fuel/air mixture).

The potential force exists BEFORE it is applied.

And so I will say it again: Horsepower is NOT a force.
 

Aussie Charger

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my peterbilt has a 400 hp cummins in it, take couple miles to reach a 100 mph at 80,000 lbs at 2300rpm, my duster makes 400 hp and takes a 1/4 mile to reach a 100 mph at 3200 lbs at 7500 rpm! whats the difference? duster got 400ish ft lbs with 4 gears of multiplication , pete got 2200 ft lbs and 13 gears of multiplication,... now tell me,..whats doing work and whats making it move?? basic 9th grade physical science!! and we got 2 threads now arguing over it, wth??
LOL! The difference is the weight.
 

273

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my peterbilt has a 400 hp cummins in it, take couple miles to reach a 100 mph at 80,000 lbs, my duster makes 400 hp and takes a 1/4 mile to reach a 100 mph at 3200 lbs! whats the difference? duster got 400ish ft lbs with 4 gears of multiplication , pete got 2200 ft lbs and 13 gears of multiplication,... now tell me,..whats doing work and whats making it move?? basic 9th grade physical science!! and we got 2 threads now arguing over it, wth??
Your duster engine could technically power your truck with a crazy amount of gearing but wouldn't last the longest.
 

Aussie Charger

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And the Cummins could power the Duster. However the Cummins has a narrow torque curve and you would waste more time changing gears. If the Duster had an electric engine with a linear torque curve with no gears, it would go faster than both!
 

dirty white boy

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Your duster engine could technically power your truck with a crazy amount of gearing but wouldn't last the longest.
use to most trucks was gas powered way back in 30s threw 50s,.. but engineers got away from that cause gas engines didnt produce enuff torque! well never did diesels till gmc blowers and holsett turbos cam about in 40s....DWB!
 

dirty white boy

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And the Cummins could power the Duster. However the Cummins has a narrow torque curve and you would waste more time changing gears. If the Duster had an electric engine with a linear torque curve with no gears, it would go faster than both!
very narrow,. 1700 to 2100 stock,..turn mine 2300 but its set up hot!
 
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