Torque vs Horsepower
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Joined: Apr 2017
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From: Plains, GA
Torque vs Horsepower
Man I get so sick of the misinformation around this. Torque is not power it is a force. I am not sure why automakers use it in the specifications. It is not a useful measure of performance. Horsepower is what gets the job done. More of it gets it done faster.
In a recent youtube video about the new Ford 3.0 powerstroke a person wrote this comment:
My comment to this was:
It is funny how my 1st Gen Cummins only has 160 hp and 400 ftlb or 122 hp at 1600 rpm but seems to do fine going down the road.
In a recent youtube video about the new Ford 3.0 powerstroke a person wrote this comment:
I know it's great that ford offers a diesel in a 1500 half ton truck. But to be honest if you have any half ton your gonna need over 300 horsepower to really be a contender and it falls short. A great looking truck but it needs more power. It needs to have V8 power numbers in that V6 turbo diesel.
Michael Bacon it puts out 440 lb ft of torque. That is more than most gas v8's. The hp is rpms. A diesel wont rev as high as a gas so it wont ever match hp. The tq is where the power is.
Diesels arnt about the power numbers there mostly about torque. This engine puts out a lit more than the v8s for towing but i also think they should keep the v8s in production
So many people just do not get the torque thing. Torque is not a measure of power it is a measure of force.
I found a post that had dyno numbers from Ford for the 5.0 and 3.7 ecoboost in the 2009-2011 engines.
I cannot find a chart for the new diesel 3.0 however I can compare these engines based on the max toruqe and hp rating of the 3.0 powerstoke.
The 3.0 powerstroke is cranking out 146 hp at 1750 rpms and 188 hp at 2250 rpms.
The 5.0 is 115hp at 2000 rpms and 149 HP at 2500 rpms. It takes 3000 rpms to get 186 hp out of the 5.0.
The diesel hp tops out at 250 hp at 3250 rpms. 250 hp fall between 3500 and 4000 rpms on the 5.0.
Now if you want to kick it and pass the 5.0 will churn out 364 hp at 5500.
So cruising in OD with the 3.0 powerstroke towing will result in lower rpms and less down shifting and better mpgs. It takes about 750 more rpms from the 5.0 to have the same power down low.
Now the 3.7 ecoboost is much more comparable. 145 hp at 2000 rpms. 197hp at 2500 rpms. 275 hp at 3500 rpms and 371 hp at 5000 rpms. The turbos give you the low end torque. Gasoline gives you the high revving hp.
I found a post that had dyno numbers from Ford for the 5.0 and 3.7 ecoboost in the 2009-2011 engines.
I cannot find a chart for the new diesel 3.0 however I can compare these engines based on the max toruqe and hp rating of the 3.0 powerstoke.
The 3.0 powerstroke is cranking out 146 hp at 1750 rpms and 188 hp at 2250 rpms.
The 5.0 is 115hp at 2000 rpms and 149 HP at 2500 rpms. It takes 3000 rpms to get 186 hp out of the 5.0.
The diesel hp tops out at 250 hp at 3250 rpms. 250 hp fall between 3500 and 4000 rpms on the 5.0.
Now if you want to kick it and pass the 5.0 will churn out 364 hp at 5500.
So cruising in OD with the 3.0 powerstroke towing will result in lower rpms and less down shifting and better mpgs. It takes about 750 more rpms from the 5.0 to have the same power down low.
Now the 3.7 ecoboost is much more comparable. 145 hp at 2000 rpms. 197hp at 2500 rpms. 275 hp at 3500 rpms and 371 hp at 5000 rpms. The turbos give you the low end torque. Gasoline gives you the high revving hp.
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From: Central VA
In racing where there's an accident, remember this; Horsepower is how fast you hit the wall. Torque is how far you move that wall. If a 300 Lb. race bike crashes into the wall at 100 MPH, Horsepower got him to hit the wall at that speed, and the wall probably won't move much.
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From: Plains, GA
Mass X Velocity would be the force moving the wall not torque. A 600 pound bike at 100 mph will move the wall in theory twice as far as a 300 pound bike.
Torque does not move anything. If you apply 50 foot pounds of torque to a bolt using a wrench and the bolt does not move there is no work done.
If 50 foot pounds of torque causes the bolt to move 1 rpm there is .010 horsepower /work done if it moves 2 rpms there is twice as much work done or .020 horsepower.
Torque does not move anything. If you apply 50 foot pounds of torque to a bolt using a wrench and the bolt does not move there is no work done.
If 50 foot pounds of torque causes the bolt to move 1 rpm there is .010 horsepower /work done if it moves 2 rpms there is twice as much work done or .020 horsepower.
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From: alaska
Simple 
Mechanical horsepower
Assuming the third CGPM (1901, CR 70) definition of standard gravity, gn=9.80665 m/s2, is used to define the pound-force as well as the kilogram force, and the international avoirdupois pound (1959), one mechanical horsepower is:
1 hp ≡ 33,000 ft-lbf/min by definition
= 550 ft⋅lbf/s since 1 min = 60 s
= 550×0.3048×0.45359237 m⋅kgf/s since 1 ft = 0.3048 m and 1 lb = 0.45359237 kg
= 76.0402249068 kgf⋅m/s
= 76.0402249068×9.80665 kg⋅m2/s3 since g = 9.80665 m/s2
= 745.69987158227022 W since 1 W ≡ 1 J/s = 1 N⋅m/s = 1 (kg⋅m/s2)⋅(m/s)
Or given that 1 hp = 550 ft⋅lbf/s, 1 ft = 0.3048 m, 1 lbf ≈ 4.448 N, 1 J = 1 N⋅m, 1 W = 1 J/s: 1 hp ≈ 746 W
Mechanical horsepower
Assuming the third CGPM (1901, CR 70) definition of standard gravity, gn=9.80665 m/s2, is used to define the pound-force as well as the kilogram force, and the international avoirdupois pound (1959), one mechanical horsepower is:
1 hp ≡ 33,000 ft-lbf/min by definition
= 550 ft⋅lbf/s since 1 min = 60 s
= 550×0.3048×0.45359237 m⋅kgf/s since 1 ft = 0.3048 m and 1 lb = 0.45359237 kg
= 76.0402249068 kgf⋅m/s
= 76.0402249068×9.80665 kg⋅m2/s3 since g = 9.80665 m/s2
= 745.69987158227022 W since 1 W ≡ 1 J/s = 1 N⋅m/s = 1 (kg⋅m/s2)⋅(m/s)
Or given that 1 hp = 550 ft⋅lbf/s, 1 ft = 0.3048 m, 1 lbf ≈ 4.448 N, 1 J = 1 N⋅m, 1 W = 1 J/s: 1 hp ≈ 746 W
Thread Starter
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From: Plains, GA
So 5 150 watt incandescent light bulbs is roughly equal to 1 horsepower
I know one of the arguments i have seen many times is big block vs small block in a drag race. Guys will always say that big block got the torque to launch it off the line. Proper gearing/ stall converter stall rpms will change this.
If the big block launch at 2,000 rpms with 376 ft lbs it is taking off with 143 hp.
Now the small block launches at 3,500 rpms with 215 ft lbs. That is also 143 hp.
That low end torque of 376 ft lbs does not mean squat with a proper setup.
I know one of the arguments i have seen many times is big block vs small block in a drag race. Guys will always say that big block got the torque to launch it off the line. Proper gearing/ stall converter stall rpms will change this.
If the big block launch at 2,000 rpms with 376 ft lbs it is taking off with 143 hp.
Now the small block launches at 3,500 rpms with 215 ft lbs. That is also 143 hp.
That low end torque of 376 ft lbs does not mean squat with a proper setup.
Thread Starter
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Joined: Apr 2017
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From: Plains, GA
Put fuel in truck tank: Make sure its the right one. My father in law filled up with gas on a 7.3PSD and drove it about 50 miles and didn't realize what was wrong! Not a cheap mistake. Had recent HEUI problems and the symptoms were the same.
put key in ignition if you can find it!
turn key
Truck go vroom hopefully!
Shift stick to "D", and push pedal down. Mine doesnt have a D LOL.
Truck move forwards !!!! As long as those drum brake adjusters don't lock up my tire LOL
put key in ignition if you can find it!
turn key
Truck go vroom hopefully!
Shift stick to "D", and push pedal down. Mine doesnt have a D LOL.
Truck move forwards !!!! As long as those drum brake adjusters don't lock up my tire LOL
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Thread Starter
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Joined: Apr 2017
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From: Plains, GA
If the 400hp vehicle is geared right, it will launch the same as the 6.
If you have two vehicles with different engines with the same gear ratio transmissions, the rear end gear ratios can be altered to get the exact same perfromance.
If you have two vehicles with different engines with the same gear ratio transmissions, the rear end gear ratios can be altered to get the exact same perfromance.
a few years back but no longer has it.
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Joined: Jun 2002
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From: Cleburne TX
Torque makes things move.
Urban Legend
Joined: Jun 2002
Posts: 365
Likes: 2
From: Cleburne TX
Just for the record I'm nether for or against V8 diesels.
I have had a friend or 2 that have owned Fords and duramax and have had no problems with them.
So this not about brand wars . A big difference is a V8 has to get revved up to produce the same torque as the old inline 6 produces at 1600 RPM.
I just ran Cummins in all of my road trucks except one and there is not any pickup manufactures that have a Cat. Wish there was.
I have had a friend or 2 that have owned Fords and duramax and have had no problems with them.
So this not about brand wars . A big difference is a V8 has to get revved up to produce the same torque as the old inline 6 produces at 1600 RPM.
I just ran Cummins in all of my road trucks except one and there is not any pickup manufactures that have a Cat. Wish there was.
