Re: [MBZ] Horse power vs. torque - was: OT: How is this game played exactly?
Now, if I understand correctly, if my pickup has the required torque to pull the 4000 lb. trailer up Grapevine, and your lawn tractor doesn't, I'll be moving and you won't. With gearing both will do the job. I've been using the terms not in a physics sense, but more in a drivability sense. I assume the normal number of gears on vehicles designed for optimal driving up to and including freeway speeds. That narrows things down a lot. My truck is on the torquey side. Carrying its 3000# camper, I can go up mild grades, and even accelerate, in 5th gear. For steeper grades I have to drop to 4th, but having done so I can still maintain any freeway speed I like. I have run into exactly one hill where I have to drop to 3rd, with a top speed of 45 (?) MPH, and that's the grade climbing out of Jackson Hole, Wyo. If I had another gear, or maybe 50 more HP or so, I could probably maintain speed going up that too. It just doesn't quite have enough torque to maintain speed going up in 4th, so I end up in 3 at redline and only partial throttle, while everybody behind me curses my name all the way up. It's narrow, steep, and windy, and only two lanes. The newer trucks would eat my lunch, I think my truck was rated maybe 200HP/300#', I think they're currently pushing 300HP/600#', and have six gears not five. -- Jim ___ http://www.okiebenz.com To search list archives http://www.okiebenz.com/archive/ To Unsubscribe or change delivery options go to: http://mail.okiebenz.com/mailman/listinfo/mercedes_okiebenz.com All posts are the result of individual contributors and as such, those individuals are responsible for the content of the post. The list owner has no control over the content of the messages of each contributor.
Re: [MBZ] Horse power vs. torque - was: OT: How is this game played exactly?
Let me suggest that your statement is more theoretical than practical. On the street, you want torque. If you are a Nascar racer on the track, you want horsepower. Randy On 29/07/2014 7:34 PM, Fmiser via Mercedes wrote: OK wrote: IIRC, the V8 has more torque, which is what a truck needs. Well, no. Not really. But sort of. Nothing against you Don, but this is a very common miss-perception. So I'm not picking on you - just using your comment as motivation to respond. *smiles* Torque is rotational force. There can be torque with no movement. Unless there is movement, no work is being done. If there is torque, and movement occurs - then work is being done. With a stopwatch (or calendar?) you can measure how fast the work is being done. This is horsepower [or watts]. If you have an engine with a fixed horsepower attached to a transmission (presuming an infinite ratio and lossless - which doesn't exist) the torque can be any value at all. For high torque, it will be moving slow - but for low torque it will be moving fast. If we don't change the diameter of the tire, the torque on the axle necessary to pull a 4000 lb [1800 kg] trailer up Grapevine out of Los Angeles is fixed. So if your your 400 hp pickup and my 7 hp garden tractor have the same size tire, the torque needed is the same. The difference is speed. Your pickup will get to the top a lot faster than my tractor because the axle can turn faster because your engine has more horsepower. So far it's very clear - but then reality rears it's ugly head. Transmissions have fixed ratios and losses. Engine ratings are for _maximum_ horsepower - but the actual horsepower and torque vary depending on speed. This makes it almost impossible to actually do an apples-to-apples comparison. Nevertheless, looking at the torque value is pretty meaningless. If you look at the torque values for various engine RPM, you can get a clue as to how usable the power is. If there is little torque at low RPM, then high RPM will be needed to get useable power. This makes it feel like the driver has to work the engine harder to get the job done. So - to repeat. Just a torque value is nearly meaningless. Torque at a particular RPM is useful - but that is by definition horsepower! -- Philip ___ ___ http://www.okiebenz.com To search list archives http://www.okiebenz.com/archive/ To Unsubscribe or change delivery options go to: http://mail.okiebenz.com/mailman/listinfo/mercedes_okiebenz.com All posts are the result of individual contributors and as such, those individuals are responsible for the content of the post. The list owner has no control over the content of the messages of each contributor.
Re: [MBZ] Horse power vs. torque - was: OT: How is this game played exactly?
Which is what pleases me about the 6spd in the F150 (and some Chevys too) which gives a nice low first and a good high 6th. -Curt From: Craig via Mercedes mercedes@okiebenz.com To: OK Don okd...@gmail.com; Mercedes Discussion List mercedes@okiebenz.com Sent: Tuesday, July 29, 2014 11:12 PM Subject: Re: [MBZ] Horse power vs. torque - was: OT: How is this game played exactly? On Tue, 29 Jul 2014 21:42:06 -0500 OK Don via Mercedes mercedes@okiebenz.com wrote: OK Phillip - thanks for the clear explanation! Now, if I understand correctly, if my pickup has the required torque to pull the 4000 lb. trailer up Grapevine, and your lawn tractor doesn't, I'll be moving and you won't. So torque does matter, but more HP with the required torque means the work gets performed faster. Insufficient torque means no work is done. No, lower torque means the work is done more slowly. With the right gearing, tires, and weight, a lawn tractor motor can move an 80,000 pound semi trailer up the Grapevine, just like a 1500 HP semi tractor. Except slower. If Curt wants to haul a load of gravel to camp, he'll need a minimum amount of torque to accomplish the job, regardless of how fast it gets done. Did I get it right? Ummm ... no, not quite. You forgot about the requisite gearing. Craig ___ http://www.okiebenz.com To search list archives http://www.okiebenz.com/archive/ To Unsubscribe or change delivery options go to: http://mail.okiebenz.com/mailman/listinfo/mercedes_okiebenz.com All posts are the result of individual contributors and as such, those individuals are responsible for the content of the post. The list owner has no control over the content of the messages of each contributor. ___ http://www.okiebenz.com To search list archives http://www.okiebenz.com/archive/ To Unsubscribe or change delivery options go to: http://mail.okiebenz.com/mailman/listinfo/mercedes_okiebenz.com All posts are the result of individual contributors and as such, those individuals are responsible for the content of the post. The list owner has no control over the content of the messages of each contributor.
Re: [MBZ] Horse power vs. torque - was: OT: How is this game played exactly?
I chose the F150 over the Chevy based first on the space behind the seat (basic, small cab) - lots in the Ford, NONE in the Chevy, and a bit more load/towing capacity. Really, it was the space behind the seat that made the difference to us. On Wed, Jul 30, 2014 at 2:25 PM, Curt Raymond via Mercedes mercedes@okiebenz.com wrote: Which is what pleases me about the 6spd in the F150 (and some Chevys too) which gives a nice low first and a good high 6th. -- OK Don NSA: The only branch of government that actually listens to US citizens! There are three kinds of men: The ones that learns by reading. The few who learn by observation. The rest of them have to pee on the electric fence for themselves. WILL ROGERS, *The Manly Wisdom of Will Rogers* 2013 F150, 18 mpg 2012 Passat TDI DSG, 44 mpg 1957 C182A, 12 mpg - but at 150 mph! ___ http://www.okiebenz.com To search list archives http://www.okiebenz.com/archive/ To Unsubscribe or change delivery options go to: http://mail.okiebenz.com/mailman/listinfo/mercedes_okiebenz.com All posts are the result of individual contributors and as such, those individuals are responsible for the content of the post. The list owner has no control over the content of the messages of each contributor.
Re: [MBZ] Horse power vs. torque - was: OT: How is this game played exactly?
Did you look at the back seat area in the Supercrew? It is huge both with the seat down and with it folded up. Randy On 30/07/2014 3:14 PM, OK Don via Mercedes wrote: I chose the F150 over the Chevy based first on the space behind the seat (basic, small cab) - lots in the Ford, NONE in the Chevy, and a bit more load/towing capacity. Really, it was the space behind the seat that made the difference to us. On Wed, Jul 30, 2014 at 2:25 PM, Curt Raymond via Mercedes mercedes@okiebenz.com wrote: Which is what pleases me about the 6spd in the F150 (and some Chevys too) which gives a nice low first and a good high 6th. ___ http://www.okiebenz.com To search list archives http://www.okiebenz.com/archive/ To Unsubscribe or change delivery options go to: http://mail.okiebenz.com/mailman/listinfo/mercedes_okiebenz.com All posts are the result of individual contributors and as such, those individuals are responsible for the content of the post. The list owner has no control over the content of the messages of each contributor.
Re: [MBZ] Horse power vs. torque - was: OT: How is this game played exactly?
OK wrote: IIRC, the V8 has more torque, which is what a truck needs. Well, no. Not really. But sort of. Nothing against you Don, but this is a very common miss-perception. So I'm not picking on you - just using your comment as motivation to respond. *smiles* Torque is rotational force. There can be torque with no movement. Unless there is movement, no work is being done. If there is torque, and movement occurs - then work is being done. With a stopwatch (or calendar?) you can measure how fast the work is being done. This is horsepower [or watts]. If you have an engine with a fixed horsepower attached to a transmission (presuming an infinite ratio and lossless - which doesn't exist) the torque can be any value at all. For high torque, it will be moving slow - but for low torque it will be moving fast. If we don't change the diameter of the tire, the torque on the axle necessary to pull a 4000 lb [1800 kg] trailer up Grapevine out of Los Angeles is fixed. So if your your 400 hp pickup and my 7 hp garden tractor have the same size tire, the torque needed is the same. The difference is speed. Your pickup will get to the top a lot faster than my tractor because the axle can turn faster because your engine has more horsepower. So far it's very clear - but then reality rears it's ugly head. Transmissions have fixed ratios and losses. Engine ratings are for _maximum_ horsepower - but the actual horsepower and torque vary depending on speed. This makes it almost impossible to actually do an apples-to-apples comparison. Nevertheless, looking at the torque value is pretty meaningless. If you look at the torque values for various engine RPM, you can get a clue as to how usable the power is. If there is little torque at low RPM, then high RPM will be needed to get useable power. This makes it feel like the driver has to work the engine harder to get the job done. So - to repeat. Just a torque value is nearly meaningless. Torque at a particular RPM is useful - but that is by definition horsepower! -- Philip ___ http://www.okiebenz.com To search list archives http://www.okiebenz.com/archive/ To Unsubscribe or change delivery options go to: http://mail.okiebenz.com/mailman/listinfo/mercedes_okiebenz.com All posts are the result of individual contributors and as such, those individuals are responsible for the content of the post. The list owner has no control over the content of the messages of each contributor.
Re: [MBZ] Horse power vs. torque - was: OT: How is this game played exactly?
OK Phillip - thanks for the clear explanation! Now, if I understand correctly, if my pickup has the required torque to pull the 4000 lb. trailer up Grapevine, and your lawn tractor doesn't, I'll be moving and you won't. So torque does matter, but more HP with the required torque means the work gets performed faster. Insufficient torque means no work is done. If Curt wants to haul a load of gravel to camp, he'll need a minimum amount of torque to accomplish the job, regardless of how fast it gets done. Did I get it right? On Tue, Jul 29, 2014 at 7:34 PM, Fmiser via Mercedes mercedes@okiebenz.com wrote: OK wrote: IIRC, the V8 has more torque, which is what a truck needs. Well, no. Not really. But sort of. Nothing against you Don, but this is a very common miss-perception. So I'm not picking on you - just using your comment as motivation to respond. *smiles* Torque is rotational force. There can be torque with no movement. Unless there is movement, no work is being done. If there is torque, and movement occurs - then work is being done. With a stopwatch (or calendar?) you can measure how fast the work is being done. This is horsepower [or watts]. If you have an engine with a fixed horsepower attached to a transmission (presuming an infinite ratio and lossless - which doesn't exist) the torque can be any value at all. For high torque, it will be moving slow - but for low torque it will be moving fast. If we don't change the diameter of the tire, the torque on the axle necessary to pull a 4000 lb [1800 kg] trailer up Grapevine out of Los Angeles is fixed. So if your your 400 hp pickup and my 7 hp garden tractor have the same size tire, the torque needed is the same. The difference is speed. Your pickup will get to the top a lot faster than my tractor because the axle can turn faster because your engine has more horsepower. So far it's very clear - but then reality rears it's ugly head. Transmissions have fixed ratios and losses. Engine ratings are for _maximum_ horsepower - but the actual horsepower and torque vary depending on speed. This makes it almost impossible to actually do an apples-to-apples comparison. Nevertheless, looking at the torque value is pretty meaningless. If you look at the torque values for various engine RPM, you can get a clue as to how usable the power is. If there is little torque at low RPM, then high RPM will be needed to get useable power. This makes it feel like the driver has to work the engine harder to get the job done. So - to repeat. Just a torque value is nearly meaningless. Torque at a particular RPM is useful - but that is by definition horsepower! -- Philip ___ http://www.okiebenz.com To search list archives http://www.okiebenz.com/archive/ To Unsubscribe or change delivery options go to: http://mail.okiebenz.com/mailman/listinfo/mercedes_okiebenz.com All posts are the result of individual contributors and as such, those individuals are responsible for the content of the post. The list owner has no control over the content of the messages of each contributor. -- OK Don NSA: The only branch of government that actually listens to US citizens! There are three kinds of men: The ones that learns by reading. The few who learn by observation. The rest of them have to pee on the electric fence for themselves. WILL ROGERS, *The Manly Wisdom of Will Rogers* 2013 F150, 18 mpg 2012 Passat TDI DSG, 44 mpg 1957 C182A, 12 mpg - but at 150 mph! ___ http://www.okiebenz.com To search list archives http://www.okiebenz.com/archive/ To Unsubscribe or change delivery options go to: http://mail.okiebenz.com/mailman/listinfo/mercedes_okiebenz.com All posts are the result of individual contributors and as such, those individuals are responsible for the content of the post. The list owner has no control over the content of the messages of each contributor.
Re: [MBZ] Horse power vs. torque - was: OT: How is this game played exactly?
On Tue, 29 Jul 2014 21:42:06 -0500 OK Don via Mercedes mercedes@okiebenz.com wrote: OK Phillip - thanks for the clear explanation! Now, if I understand correctly, if my pickup has the required torque to pull the 4000 lb. trailer up Grapevine, and your lawn tractor doesn't, I'll be moving and you won't. So torque does matter, but more HP with the required torque means the work gets performed faster. Insufficient torque means no work is done. No, lower torque means the work is done more slowly. With the right gearing, tires, and weight, a lawn tractor motor can move an 80,000 pound semi trailer up the Grapevine, just like a 1500 HP semi tractor. Except slower. If Curt wants to haul a load of gravel to camp, he'll need a minimum amount of torque to accomplish the job, regardless of how fast it gets done. Did I get it right? Ummm ... no, not quite. You forgot about the requisite gearing. Craig ___ http://www.okiebenz.com To search list archives http://www.okiebenz.com/archive/ To Unsubscribe or change delivery options go to: http://mail.okiebenz.com/mailman/listinfo/mercedes_okiebenz.com All posts are the result of individual contributors and as such, those individuals are responsible for the content of the post. The list owner has no control over the content of the messages of each contributor.
Re: [MBZ] Horse power vs. torque - was: OT: How is this game played exactly?
OK wrote: Now, if I understand correctly, if my pickup has the required torque to pull the 4000 lb. trailer up Grapevine, and your lawn tractor doesn't, I'll be moving and you won't. So torque does matter, but more HP with the required torque means the work gets performed faster. Insufficient torque means no work is done. Pretty close. What you describe would be correct if it were not for the transmission. However, the transmission trades speed and torque (much like a electric transformer trades volts and amps - but the watts stay the same). So a 'phone vibration motor connected through a transmission with a deep enough low gear could pull that trailer up Grapevine! Probably we would have to measure the speed by years or decades, though. *smiles* This means that my little tractor, with it's very, very low gearing will be able to pull the trailer because the transmission is trading away speed until there is enough torque. But with only 7 HP, the speed will be very slow. If Curt wants to haul a load of gravel to camp, he'll need a minimum amount of torque to accomplish the job, regardless of how fast it gets done. Did I get it right? Just remember that the lower gear ratios of the transmission _increase_ torque and _decrease_ speed. So if there isn't enough torque - downshift. Of course, that only works until you run out of gears... Higher horsepower means higher speed at the torque needed to do the job. Usually - as that ugly headed real-world gets in the way and messes this all up with transmission ratios that don't line up well to engine power band, torque curves over RPM, etc. Nothing is as simple as simple physics says it should be! -- Philip ___ http://www.okiebenz.com To search list archives http://www.okiebenz.com/archive/ To Unsubscribe or change delivery options go to: http://mail.okiebenz.com/mailman/listinfo/mercedes_okiebenz.com All posts are the result of individual contributors and as such, those individuals are responsible for the content of the post. The list owner has no control over the content of the messages of each contributor.
