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Old 07-28-2015, 03:48 PM   #401
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Originally Posted by turbofan View Post
Put 10k pounds behind an ecodiesel ram and the same weight behind a 2.7 ecoboost and see which one can top the hill at a higher speed. I'd put my money on the Ram.
Pay up:

click to 14:29 (9m07s, "it went up pretty slow"):

click to 12:32 (7m38s, "we could have gone faster but didn't want to break the speed limit"):

Last edited by Savington; 07-28-2015 at 04:04 PM.
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Old 07-28-2015, 03:51 PM   #402
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18 wheelers with 450hp and 2000lbft would beg to differ. There's a reason high torque diesel trucks are kings of heavy towing...
They are designed to be efficient at high power levels under continuous duty and last a long time doing it, that's where the big rig diesel engines shine. To make 400HP with that level of efficiency requires a big engine, lots of boost, and low REVs, and a lot more.
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Old 07-28-2015, 03:53 PM   #403
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... HP doesn't matter when you don't need to go above 2k rpms
LOL. Amazing some of the comments here!
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Old 07-28-2015, 03:57 PM   #404
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I want to make a super clear point here: Horsepower is what moves vehicles. Torque does not. This is a factual statement that isn't open to interpretation or opinion. When you make lots of torque at a low RPM, you end up with an engine that makes good horsepower at low RPM. This is why they feel "torquey" - the extra power delivered at a lower RPM makes the car accelerate faster than it otherwise would. Marketing doublespeak has trained us to look at torque, but in reality the only reason a high-torque engine accelerates a vehicle faster at low RPM than a low-torque engine does is because the high-torque engine makes more horsepower.

When you look at the semi rig industry, the trend is towards horsepower. 300hp and 400hp engines are giving way to 600 and 700hp engines, and when you look at logging trucks or oversize load trucks, they always have more horsepower. They need huge torque because they don't spin the engine very fast (for longevity/efficiency), and thus the engine has to be huge. You could absolutely pull 80,000lbs up a hill with a 400hp small-displacement gas engine, as long as you gear it appropriately and ensure that it remains at peak power. Getting that load moving from idle would be painful, which is why semi rigs use huge engines with lots of horsepower at idle as well.
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Old 07-28-2015, 03:57 PM   #405
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....
I'm sure the Honda was designed to get better mileage when not towing, but it doesn't do both well.
Exactly. The honda was doing what it was designed to do, which is max gas mileage and comfort but can technically tow something at the expense of efficiency without breaking.

It's almost like vehicles are designed with certain goals in mind when they are built, with priority to certain aspects?
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Old 07-28-2015, 03:57 PM   #406
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LOL. Amazing some of the comments here!
Do explain. When I tow it's not a contest of how fast I can get somewhere, it's of how comfortably I can maintain a speed and how safely I can control the load. So I set the cruise on the 6.7L diesel and it very very rarely leaves overdrive.
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Old 07-28-2015, 04:00 PM   #407
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I want to make a super clear point here: Horsepower is what moves vehicles. Torque does not. This is a factual statement that isn't open to interpretation or opinion. When you make lots of torque at a low RPM, you end up with an engine that makes good horsepower at low RPM. This is why they feel "torquey" - the extra power delivered at a lower RPM makes the car accelerate faster than it otherwise would. Marketing doublespeak has trained us to look at torque, but in reality the only reason a high-torque engine accelerates a vehicle faster at low RPM than a low-torque engine does is because the high-torque engine makes more horsepower.

When you look at the semi rig industry, the trend is towards horsepower. 300hp and 400hp engines are giving way to 600 and 700hp engines, and when you look at logging trucks or oversize load trucks, they always have more horsepower. They need huge torque because they don't spin the engine very fast (for longevity/efficiency), and thus the engine has to be huge. You could absolutely pull 80,000lbs up a hill with a 400hp small-displacement gas engine, as long as you gear it appropriately and ensure that it remains at peak power. Getting that load moving from idle would be painful, which is why semi rigs use huge engines with lots of horsepower at idle as well.
Also why they have so many gears, since they have a low rev range and carry very heavy loads.

I still think it's crazy how people don't understand the difference between HP and Torque but claim they do. Makes for a great read.
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Old 07-28-2015, 04:01 PM   #408
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<p>He means that the reason you don't have to leave overdrive is because you have a lot of horsepower at 2k. Horsepower is a direct relationship to torque.</p>
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Old 07-28-2015, 04:02 PM   #409
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video stuff
</p><p>Why does the dodge have a shield (or whatever) on the trailer and the ford doesnt?</p>
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Old 07-28-2015, 04:03 PM   #410
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Do explain. When I tow it's not a contest of how fast I can get somewhere, it's of how comfortably I can maintain a speed and how safely I can control the load. So I set the cruise on the 6.7L diesel and it very very rarely leaves overdrive.
You should look up the HP of that motor at the RPM you tow at in overdrive. That HP level is enough to move your rig. It takes a certain amount of power to move your truck. Wind resistance, rolling drag, geartrain losses, all of this for the trailer too. Add it up and it might be 30HP or it might be 250HP when going up a hill. If you motor can make the required HP at that RPM, then it won't downshift. If it can't, it will downshift.
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Old 07-28-2015, 04:08 PM   #411
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<p></p><p>Why does the dodge have a shield (or whatever) on the trailer and the ford doesnt?</p>
Maybe the Ford went so fast it flew off
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Old 07-28-2015, 04:10 PM   #412
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<p>I hate the guy in the passenger seat with a ******* passion. I used to watch a lot more fast lane truck stuff and he just pisses me off so much I can't do it anymore.</p>
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Old 07-28-2015, 04:13 PM   #413
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I hate them both, and there's a huge amount of false technical interpretation in every single one of those videos, but Ed asked for a Ram and an F150 towing 10k up a hill, and that's exactly what TFL does with pretty much every truck on the market.
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Old 07-28-2015, 04:16 PM   #414
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false technical interpretation in every single one of those videos
</p><p>Also how are they accurate when there are other people on the road.</p><p><img src="http://cimg3.ibsrv.net/gimg/www.miataturbo.net-vbulletin/1220x924/80-grinds_my_gears_ccd0ab0520137425eef7ecb66d70e4658a fdd08b.png" title="" /><br /><br />&nbsp;</p>
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Old 07-28-2015, 06:24 PM   #415
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If you're towing 10k lbs, wouldn't you rather have the 6k lb truck?

It seems a 10k trailer would push a 4500 lb truck around.

I don't think I'd regularly want to tow a load >2x the weight of the tow vehicle...
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Old 07-28-2015, 06:45 PM   #416
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<p>Isn't the argument between whether it's HP or Torque moving the load really just semantics? I mean, A vehicle that makes a lot of low RPM torque has low RPM horsepower, and a vehicle that makes a lot of high RPM horsepower also shows torque at those high RPMs. What's the difference, and the point of arguing the difference?</p><p>And indeed, good thing I didn't bet real money cuz I'd have lost some of it.</p><p>That being said, that rock guard would absolutely affect the way it tows at high speeds. It's not an apples to apples comparison. But the Ram does seem a bit disappointing.</p>
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Old 07-28-2015, 06:48 PM   #417
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<p>Isn't the argument between whether it's HP or Torque moving the load really just semantics? I mean, A vehicle that makes a lot of low RPM torque has low RPM horsepower, and a vehicle that makes a lot of high RPM horsepower also shows torque at those high RPMs. What's the difference, and the point of arguing the difference?</p><p>And indeed, good thing I didn't bet real money cuz I'd have lost some of it.</p><p>That being said, that rock guard would absolutely affect the way it tows at high speeds. But the Ram does seem a bit disappointing.</p>
HP is a unit of power.

Torque is not.

They are two different things. Torque is a force, HP is a force multiplied by a distance. That's what has been pointed out, as saying things like "HP doesn't matter" is wrong.
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Old 07-28-2015, 07:10 PM   #418
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<p>Isn't the argument between whether it's HP or Torque moving the load really just semantics?
No. It's an important distinction. 2000ft.lbs of torque at 1200rpm moves lots of things. 1000ft.lbs of torque at 2400rpm (or 500ft.lbs at 4800rpm, or 250ft.lbs at 9600rpm) moves the exact same quantity of things at the exact same velocity. Half the torque (or 25% or 12.5%), but the exact same power, and thus the exact same work being done.
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Old 07-28-2015, 07:10 PM   #419
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Originally Posted by Efini~FC3S View Post
If you're towing 10k lbs, wouldn't you rather have the 6k lb truck?

It seems a 10k trailer would push a 4500 lb truck around.

I don't think I'd regularly want to tow a load >2x the weight of the tow vehicle...
Sure, but I also like my 6k lb trucks to be 3/4 ton trucks instead of another fat Chrysler product.

As you should too since you pay for GCVW in NC.

Last edited by FatKao; 07-28-2015 at 07:27 PM.
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Old 07-28-2015, 07:28 PM   #420
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Originally Posted by Savington View Post
I want to make a super clear point here: Horsepower is what moves vehicles. Torque does not. This is a factual statement that isn't open to interpretation or opinion. When you make lots of torque at a low RPM, you end up with an engine that makes good horsepower at low RPM. This is why they feel "torquey" - the extra power delivered at a lower RPM makes the car accelerate faster than it otherwise would. Marketing doublespeak has trained us to look at torque, but in reality the only reason a high-torque engine accelerates a vehicle faster at low RPM than a low-torque engine does is because the high-torque engine makes more horsepower.

When you look at the semi rig industry, the trend is towards horsepower. 300hp and 400hp engines are giving way to 600 and 700hp engines, and when you look at logging trucks or oversize load trucks, they always have more horsepower. They need huge torque because they don't spin the engine very fast (for longevity/efficiency), and thus the engine has to be huge. You could absolutely pull 80,000lbs up a hill with a 400hp small-displacement gas engine, as long as you gear it appropriately and ensure that it remains at peak power. Getting that load moving from idle would be painful, which is why semi rigs use huge engines with lots of horsepower at idle as well.
Force is what moves an object (in this case, a vehicle). Torque is a force applied to rotate an object about an axis. Technically speaking, torque is what moves an object.

Horsepower is measure of torque applied over time. HP = Torque x RPM 5252 .

If you took a little RC plane motor and asked it to move a 80,000lb vehicle wheel it is possible to do with astronomical, no loss gearing. In so doing, you have massively increased the torque applied to the wheels.

If you took a 80,000lb vehicle motor and asked it to move an RC plane prop, it is possible to do with gearing. In so doing, you have decreased the torque applied to the prop. The RC plane won't fly however.

So, you make design choices appropriate to your vehicle and needs. Horsepower is the more relevant factor to move most road vehicles quickly. Increasing the horsepower, as is the trend today, allows more work to be done in the same or similar packaging. This is allowed by advanced materials and engineering practices used today. I would change this though and say the trend today is combustion efficiency.

Trying to simplify the argument into "Torque wins bra" vs "Horepower is badass bra" eschews a fundamental understanding of applied torque at the wheel, work, gearing, & horsepower pervasive on forums.

Here is one website that goes over some details.
Power and Torque: Understanding the Relationship Between the Two, by EPI Inc.
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