Help explaining horsepower and torque feel

[SplawnDarts]

You don't even vaguely understand how a dyno works. Trying to educate you has proved futile. So you get yo just keep being ignorant

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[Jackson1320]

Yes. The key point though is that HP is gearing-independent. When you gear down by say a 2x ratio, you double the torque and halve the RPM. If all you look at is torque, you'd think you'd doubled your output but of course that's not true.

That is true. You have Doubled your output mechanically with gear ratio.

You don't even vaguely understand how a dyno works. Trying to educate you has proved futile. So you get yo just keep being ignorant

Maybe you can grow up a little bit and try and have a conversation without insulting people. I’m trying to talk to you and understand. you’re trying to insult and be an asshole. So who is ignorant

 

[Jackson1320]

You don't even vaguely understand how a dyno works. Trying to educate you has proved futile. So you get yo just keep being ignorant

I understand exactly how a Dyno works. which is why I do not understand what you are saying

 

[SplawnDarts]

That is true. You have Doubled your output mechanically with gear ratio.

Quick, Jackson1320 is giving away free lunches. Why not gear down 1000x and have THE MOST POWERFUL ENGINE ON THE PLANET?!?!?

Seriously, you need to look back at that equation you don't understand that relates HP and torque. When you gear down by a factor of N, you get N times the torque at 1/N of the RPM. You gain nothing, except the option to operate at a different RPM that may or may not be better for your engine. There is no free lunch, no matter what you might think. Power is what matters. Torque is a function of gearing choice and can be manipulated arbitrarily.

 

[SplawnDarts]

I understand exactly how a Dyno works. which is why I do not understand what you are saying

Oh that's quite clear - you lack the physics understanding to understand this discussion.

 

[K4fxd]

To put this in the real world the first gen F150 5.0 ran the 1/4 around 14.3 at 96 MPH.

The ecoboost F150 ran the 1/4 around 13.9 at 89 MPH

The eco has more torque and the coyote has more horsepower.

 

[SplawnDarts]

Or put another way, given a few maritime reduction drives I could easily make a 1 million lb-ft coyote. Just reduce the output speed by a factor of about 2400. Now the question is would this engine be of any use in accelerating your car faster? Would it give you 1 million units of acceleration where the old engine gave you only 400? Of course not, because while the output shaft on the engine would have insane torque (too much - it would demolish transmissions, motor mounts etc.) it would only turn the output shaft over about 3 times a minute.

Torque does not matter - you can make the number be whatever you want via gearing. What matters is power - HP.

 

[K4fxd]

But you could put 6 foot tires on it and plow a field.

 

[SplawnDarts]

To put this in the real world the first gen F150 5.0 ran the 1/4 around 14.3 at 96 MPH.

The ecoboost F150 ran the 1/4 around 13.9 at 89 MPH

The eco has more torque and the coyote has more horsepower.

This has everything to do with traction/launch and transmission issues, which is why the ETs and trap speeds are reversed. It tells you essentially nothing about the engines.

 

[K4fxd]

No, torque is quicker, HP is faster. If the eco had the same HP as the coyote the trap speed would be the same.

 

[engineermike]

Gearing can only multiply torque, not power.

One if my favorite examples is the M1 Abrams tank engine that produces 1500 hp and only 500 ftlb of torque. By the time it goes through numerous gear reducers it’s making 210,000 ftlb at the rear, ahem, tracks. But still only 1500 hp.

If you tell me the time it takes your car to accelerate from speed a to speed b and the weight, I can tell you the power it made. I only need the gear ratio to calculate the torque. Tell me which one is calculated from which then...

 

[K4fxd]

I was shocked as a kid when I found out our Farmal H tractor only had 30 HP or so. It pulled a 4 row plow without breaking a sweat.

 

[Jackson1320]

Quick, Jackson1320 is giving away free lunches. Why not gear down 1000x and have THE MOST POWERFUL ENGINE ON THE PLANET?!?!?

Seriously, you need to look back at that equation you don't understand that relates HP and torque. When you gear down by a factor of N, you get N times the torque at 1/N of the RPM. You gain nothing, except the option to operate at a different RPM that may or may not be better for your engine. There is no free lunch, no matter what you might think. Power is what matters. Torque is a function of gearing choice and can be manipulated arbitrarily.

That is exactly what a transfer case does. Uses gear ratio to multiply torque. I never said anything about free. I don’t understand how any of your smartass comments explain how horsepower is a better way to calculate a engines power. When horsepower is dependent on torque? Pretend for one second that you are a adult and act like it.

 

[engineermike]

That said, I’ve owned both combinations of torque and power...the SOTP difference to me is a higher torque, lower power setup hits hard then falls off. Every time you shift, it puts you back in the seat again. A higher hp, lower torque still hits hard if geared correctly, but never falls off with rpm.

 

[engineermike]

... explain how horsepower is a better way to calculate a engines power....

Errrr...

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