Foot lbs or Pound ft = torque?
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I like what mythbusters did with figuring what the difference was between a car hitting a solid wall at 60 mph versus 2 cars going 60 hitting each other, approach speed 120.
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Yup. The math and physics of collisions are indisputable. I've given up having this discussion with guys who don't/won't get it.
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Be assured that I'm impressed with the knowledge presented here ... My mathematical skills were at their highest point my Junior year in High School and that was well over 50 years ago .... Algebra I, Geometry and Algebra II were as far as I went
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Now that we are arguing where the lines cross. The TQ and HP numbers are always equal at 5252 - period - that's a function of the formula.
If HP is scaled to A and TQ is scaled to B, then visually it will not appear that the lines cross when plotted on one sheet of paper because you are plotting two different scales on one graph and you MUST reference the scales.
No matter how they are scaled, if you look at the TQ value at 5252 and the HP value at 5252 they will be equal - again - that's the math.
So, if this is a semantics argument, the values are always equal at 5252. For them to visually appear as crossing at 5252 looking only at the lines and not the scales, the scales need to be equal. Once more and say it with me...the values are always equal at 5252 - that's the math.
If HP is scaled to A and TQ is scaled to B, then visually it will not appear that the lines cross when plotted on one sheet of paper because you are plotting two different scales on one graph and you MUST reference the scales.
No matter how they are scaled, if you look at the TQ value at 5252 and the HP value at 5252 they will be equal - again - that's the math.
So, if this is a semantics argument, the values are always equal at 5252. For them to visually appear as crossing at 5252 looking only at the lines and not the scales, the scales need to be equal. Once more and say it with me...the values are always equal at 5252 - that's the math.
Last edited by Ed Ramberger; Apr 23, 2022 at 10:16 AM.
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Know the best thing about math in summer school? ALL the best looking blondes, and I do mean ALL, from four different surrounding high schools were all in those classes.
You know what they say about blondes. Its generally true.
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You are absolutely correct that HP=(RPMxT)/5252, and then solving for T: T=(HPx5252)/RPM. The constant 5252 appears in BOTH. That is the commonality between the two equations, because while torque, horsepower and rpm all vary, 5252 never changes.
Because the constant 5252 never changes and appears in both equations, the lines will ALWAYS cross at 5252. They cannot cross anywhere else, because that is the only constant that appears in both equations.
If the scales for hp and t are not the same, then the lines will be either flatter or more curved, steeper or less steep, but they will always cross at 5252.
Last edited by IdahoHacker; Apr 23, 2022 at 12:08 PM.
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I don't believe this is correct, and I did a lot of graphing of mathematical equations back in the day.
You are absolutely correct that HP=(RPMxT)/5252, and then solving for T: T=(HPx5252)/RPM. The constant 5252 appears in BOTH. That is the commonality between the two equations, because while torque, horsepower and rpm all vary, 5252 never changes.
Because the constant 5252 never changes and appears in both equations, the lines will ALWAYS cross at 5252. They cannot cross anywhere else, because that is the only constant that appears in both equations.
If the scales for hp and t are not the same, then the lines will be either flatter or more curved, steeper or less steep, but they will always cross at 5252.
You are absolutely correct that HP=(RPMxT)/5252, and then solving for T: T=(HPx5252)/RPM. The constant 5252 appears in BOTH. That is the commonality between the two equations, because while torque, horsepower and rpm all vary, 5252 never changes.
Because the constant 5252 never changes and appears in both equations, the lines will ALWAYS cross at 5252. They cannot cross anywhere else, because that is the only constant that appears in both equations.
If the scales for hp and t are not the same, then the lines will be either flatter or more curved, steeper or less steep, but they will always cross at 5252.
The bottom line is that if you have HP scaled to 100 and TQ scaled to 150, the lines wont visually intersect on a graph because you are graphing two scales on top of each other. If you look at the HP value at 5252 and the TQ value at 5252 they will be equal. Thats a cold hard fact.
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Joined: Jun 2018
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From: WI
OK gentlemen, I do agree on 5252. However, I do know that I have 119 lb/ ft of torque and 104 hp at the rear wheel of my 103ci. It was explained to me from a very reputable builder on this form that that is not possible. Would one of you please explain why and how that is possible, so the unnamed individual can understand that it is possible. Thanks guys for everything, I never thought this post would go this far, but I’m glad it has. Just because someone says dyno curves can't happen that way, does not make their statement gospel********
Scienta Potentia est.....
Scienta Potentia est.....Last edited by Harley1004; Apr 23, 2022 at 01:08 PM.