Foot lbs or Pound ft = torque?
Seasoned HDF Member
Joined: Dec 2005
Posts: 19,940
Likes: 8,037
From: poway
I don't believe that is correct. You're kinda mixing the two things. Lb-ft is torque, and torque has no rate, or time component. Torque is a force times a lever arm. There is no time involved.
Ft-lbs is work, and work also has no rate, or time component. You move a certain weight a certain distance, and work has been done. It doesn't matter how long it takes. Time has nothing to do with work.
Power most definitely has a rate or time component. The faster you do work, the more power. But, you don't: "Take ft-lbs and add rate, and it becomes the same thing, power." Ft-lbs is torque, not work, and you can't add time to torque, and torque has nothing to do with power.
Ft-lbs is work, and work also has no rate, or time component. You move a certain weight a certain distance, and work has been done. It doesn't matter how long it takes. Time has nothing to do with work.
Power most definitely has a rate or time component. The faster you do work, the more power. But, you don't: "Take ft-lbs and add rate, and it becomes the same thing, power." Ft-lbs is torque, not work, and you can't add time to torque, and torque has nothing to do with power.
Yeah, you are right.. I'll fall back more of a definition thing here..
Club Member
Joined: Jul 2014
Posts: 11,470
Likes: 3,572
From: Idaho
Thread Starter
|
Stellar HDF Member
Joined: Jun 2018
Posts: 2,296
Likes: 494
From: WI
Thread Starter
|
Stellar HDF Member
Joined: Jun 2018
Posts: 2,296
Likes: 494
From: WI
I had a very respected Harley Davidson motorcycle engine builder/designer tell me that I was incorrect when I told him my Dyno Numbers. The end result of my build was 119 lb-ft of torque, and only 104 hp from my 103 in.ł twin cam.
Let me ask all of you this: when I hook up my 6 cylinder 375 hp Peterbilt to my 48 foot trailer and the trailer is loaded with 45,000 pounds of weight. How is it possible that a 375 hp motor will get me to 75 or 80 miles an hour pretty quickly with that much weight?
I have a v8 410hp pickup truck, if I hooked my pick up truck to my 48 foot trailer with 45,000 pounds on it,
I would probably never be able to get that loaded trailer up to 35/40 mph. And if that little truck could, it would probably take it an hour to get there. Hell, that’s 35 more horsepower in the little truck versus the big truck. I know One engine runs on diesel fuel, the other one runs on gasoline.: Diesel engines do make more lb-ft of torque than gasoline engines, however:
My Diesel engine puts out over 1500 lb-ft of torque. Regardless of what fuel is used, it is most certainly possible to make more torque then you do horsepower, no matter what type of fuel you explode or 🔥 burn.
5252 is the magical number in physics where Horsepower and torque MEET…S.A.E. But that doesn’t mean it’s the only number where those two Figures cross each other on a Dyno.
There is an engine builder on this forum that has said, “if you ain’t got torque, how much horsepower you’ve got reeeeeeally doesn*t matter! Personally, I couldn’t agree more!
Let me ask all of you this: when I hook up my 6 cylinder 375 hp Peterbilt to my 48 foot trailer and the trailer is loaded with 45,000 pounds of weight. How is it possible that a 375 hp motor will get me to 75 or 80 miles an hour pretty quickly with that much weight?
I have a v8 410hp pickup truck, if I hooked my pick up truck to my 48 foot trailer with 45,000 pounds on it,
I would probably never be able to get that loaded trailer up to 35/40 mph. And if that little truck could, it would probably take it an hour to get there. Hell, that’s 35 more horsepower in the little truck versus the big truck. I know One engine runs on diesel fuel, the other one runs on gasoline.: Diesel engines do make more lb-ft of torque than gasoline engines, however:
My Diesel engine puts out over 1500 lb-ft of torque. Regardless of what fuel is used, it is most certainly possible to make more torque then you do horsepower, no matter what type of fuel you explode or 🔥 burn.
5252 is the magical number in physics where Horsepower and torque MEET…S.A.E. But that doesn’t mean it’s the only number where those two Figures cross each other on a Dyno.
There is an engine builder on this forum that has said, “if you ain’t got torque, how much horsepower you’ve got reeeeeeally doesn*t matter! Personally, I couldn’t agree more!
Last edited by Harley1004; Apr 23, 2022 at 12:31 AM.
Tourer
Joined: May 2006
Posts: 269
Likes: 100
From: Florida
The torque and HP must be scaled the same on the graph or they won't cross at 5252.
Last edited by billgran; Apr 23, 2022 at 07:56 AM.
Seasoned HDF Member
Joined: Dec 2005
Posts: 19,940
Likes: 8,037
From: poway
I had a very respected Harley Davidson motorcycle engine builder/designer tell me that I was incorrect when I told him my Dyno Numbers. The end result of my build was 119 lb-ft of torque, and only 104 hp from my 103 in.ł twin cam.
Let me ask all of you this: when I hook up my 6 cylinder 375 hp Peterbilt to my 48 foot trailer and the trailer is loaded with 45,000 pounds of weight. How is it possible that a 375 hp motor will get me to 75 or 80 miles an hour pretty quickly with that much weight?
I have a v8 410hp pickup truck, if I hooked my pick up truck to my 48 foot trailer with 45,000 pounds on it,
I would probably never be able to get that loaded trailer up to 35/40 mph. And if that little truck could, it would probably take it an hour to get there. Hell, thats 35 more horsepower in the little truck versus the big truck. I know One engine runs on diesel fuel, the other one runs on gasoline.: Diesel engines do make more lb-ft of torque than gasoline engines, however:
My Diesel engine puts out over 1500 lb-ft of torque. Regardless of what fuel is used, it is most certainly possible to make more torque then you do horsepower, no matter what type of fuel you explode or 🔥 burn.
5252 is the magical number in physics where Horsepower and torque MEET S.A.E. But that doesnt mean its the only number where those two Figures cross each other on a Dyno.
There is an engine builder on this forum that has said, if you aint got torque, how much horsepower youve got reeeeeeally doesn*t matter! Personally, I couldnt agree more!
Let me ask all of you this: when I hook up my 6 cylinder 375 hp Peterbilt to my 48 foot trailer and the trailer is loaded with 45,000 pounds of weight. How is it possible that a 375 hp motor will get me to 75 or 80 miles an hour pretty quickly with that much weight?
I have a v8 410hp pickup truck, if I hooked my pick up truck to my 48 foot trailer with 45,000 pounds on it,
I would probably never be able to get that loaded trailer up to 35/40 mph. And if that little truck could, it would probably take it an hour to get there. Hell, thats 35 more horsepower in the little truck versus the big truck. I know One engine runs on diesel fuel, the other one runs on gasoline.: Diesel engines do make more lb-ft of torque than gasoline engines, however:
My Diesel engine puts out over 1500 lb-ft of torque. Regardless of what fuel is used, it is most certainly possible to make more torque then you do horsepower, no matter what type of fuel you explode or 🔥 burn.
5252 is the magical number in physics where Horsepower and torque MEET S.A.E. But that doesnt mean its the only number where those two Figures cross each other on a Dyno.
There is an engine builder on this forum that has said, if you aint got torque, how much horsepower youve got reeeeeeally doesn*t matter! Personally, I couldnt agree more!
You did you measure the HP at the rear wheel? How meny speeds did each have in the tranny? What type of tranny. It's all about converting power to force at the rear wheel.
Why is that I can get my bobber off the faster than a GSXR 1000 but by the end of second gear the GSXR passes me?
HD Forum Stories
The Best of Harley-Davidson for Lifelong Riders
7 Times Harley-Davidson Chucked Tradition Out the Window
Verdad Gallardo
7 Surprising Harley-Davidson Products that Are Not Motorcycles
Verdad Gallardo
8 Best Harley-Davidson Motorcycles Ever
Pouria Savadkouei
10 Worst Harley-Davidson Motorcycles Ever
Pouria Savadkouei
Killer Custom's Jail Break Is The Breakout That Refused to Blend In
Verdad Gallardo
Crazy Bunderbike Build Looks Amazing, But Is It Impossible to Ride?
Verdad Gallardo
Harley-Davidson Reveals Super Cool Cafe Racer Concept
Verdad Gallardo
Engraved Rebellion: Inside Bundnerbike's Glam Rock II
Verdad Gallardo
10 Motorcycles You Should Never Buy
Joe Kucinski
Seasoned HDF Member
Joined: Jan 2011
Posts: 157,527
Likes: 57,084
From: Michigan 15 Minutes East Of Hell
You did you measure the HP at the rear wheel? How meny speeds did each have in the tranny? What type of tranny. It's all about converting power to force at the rear wheel.
Why is that I can get my bobber off the faster than a GSXR 1000 but by the end of second gear the GSXR passes me?
Why is that I can get my bobber off the faster than a GSXR 1000 but by the end of second gear the GSXR passes me?
