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OMG! 
Power = Torque X RPM
and in electricity:
Power = VOLT X AMP
And in fluid mechanics:
Power = Pressure X Flow
and in mechanics (linear):
Power = Force X Velocity
See - in any case - power is proportional to a force applied (Torque, VOLT, Pressure, Force) AND the rate at which that force is delivered (RPM, AMP, Flow, Velocity). And 1 mechanical HP = 1 electrical HP; Because power is a unit of measure that represents the same thing, no matter where you apply it.
I have come to the conclusion in my book a pound is not a pound and a motor that have more volume is heavier pound for pound..
If you keep the same density, yes, a larger motor will be heavier. But if we assume that they have the same mass (in pounds), then two motors can have different volumes if they have different densities (for example, one is made of aluminum and the other one made of cast iron). This is true because:
Mass = Volume X Density
which is the same mathematical relationship as
Power = Torque X RPM
1 lb of aluminum is 1 lb of cast iron is 1 lb of water is 1 lb of air is 1 lb of ... anything! The volume occupied by this mass depends of the density of the material.
Similarly, 1 hp is 1 hp, no matter where it comes from. The torque needed to produce that 1 hp depends on the RPM at which it is produced.
This very fundamental mathematical concept holds everywhere, in every field. Hydroelectric power stations, satellites sent in space, ballistics, name it: They are all parts of science based on that principle. Do you really think engine building is the black sheep of science that do not follow the proven laws of physics?
It doesn't mean they don't know how to build good and powerful engines, but they cannot explain why and how in terms of physics. And people used to build a lot of great stuff before understanding what we know now. But we were able to improve ourselves once we begun understanding what we were doing.
Don't fear the knowledge, it will open your mind to a wonderful world.
Read (and re-read) carefully the link by @Ketch22 in post #92. Make it your bible, because that is engine building based on an understanding of physics.

You don't need many gears to get the torque, you need many gears to extend your speed range.Moretorque said:They are the ones saying it would have to have a tranny with many many gears
If you need to know at what RPM is your torque, that means that you are looking for HP; Because Power = Torque X RPM. If they didn't knew the RPM, torque alone is a useless number to determine performance (and vice versa). HP is a unit that was created just for that: Evaluating the effect of the torque combined with RPM.Moretorque said:They do not care what the HP # is for the most part they want to know how much torque and at what RPM
Tell that to a professional Top Fuel dragster or a Formula One engine builder; Then see who will laugh ...Moretorque said:when they look for more power they look for more torque to get it and not more RPM spin.
Actually, torque is to HP what VOLTs are to electricity. AMPs is related to RPM. And - look at that - in mechanics:Moretorque said:Torque is to HP what AMPs are to electricity,
Power = Torque X RPM
and in electricity:
Power = VOLT X AMP
And in fluid mechanics:
Power = Pressure X Flow
and in mechanics (linear):
Power = Force X Velocity
See - in any case - power is proportional to a force applied (Torque, VOLT, Pressure, Force) AND the rate at which that force is delivered (RPM, AMP, Flow, Velocity). And 1 mechanical HP = 1 electrical HP; Because power is a unit of measure that represents the same thing, no matter where you apply it.
Again, HP is unit of measure, it's a definition. Let me show you how silly the sentence you wrote sounds like:Moretorque said:I have come to the conclusion in my book HP is not HP and a motor that does it's work at lower RPM is more powerful HP for HP..
I have come to the conclusion in my book a pound is not a pound and a motor that have more volume is heavier pound for pound..
If you keep the same density, yes, a larger motor will be heavier. But if we assume that they have the same mass (in pounds), then two motors can have different volumes if they have different densities (for example, one is made of aluminum and the other one made of cast iron). This is true because:
Mass = Volume X Density
which is the same mathematical relationship as
Power = Torque X RPM
1 lb of aluminum is 1 lb of cast iron is 1 lb of water is 1 lb of air is 1 lb of ... anything! The volume occupied by this mass depends of the density of the material.
Similarly, 1 hp is 1 hp, no matter where it comes from. The torque needed to produce that 1 hp depends on the RPM at which it is produced.
This very fundamental mathematical concept holds everywhere, in every field. Hydroelectric power stations, satellites sent in space, ballistics, name it: They are all parts of science based on that principle. Do you really think engine building is the black sheep of science that do not follow the proven laws of physics?
If they do laugh, it is because they don't understand physics. They usually can build only one type of engine (V8, I4, Chevy, Honda, etc.), because they mostly monkey what others around them have done more than they understand what they are doing.Moretorque said:When I tell motor buiulders there are people out there saying you can move 40 tons down the highway at a good clip with a small block car motor HP being equal they practically laugh.
It doesn't mean they don't know how to build good and powerful engines, but they cannot explain why and how in terms of physics. And people used to build a lot of great stuff before understanding what we know now. But we were able to improve ourselves once we begun understanding what we were doing.
Don't fear the knowledge, it will open your mind to a wonderful world.
Read (and re-read) carefully the link by @Ketch22 in post #92. Make it your bible, because that is engine building based on an understanding of physics.