โMar-06-2014 04:04 PM
โMar-18-2014 08:59 AM
OhhWell wrote:I'll let my posts stand. Just stating you know physics, and that horsepower is horsepower, and that Caterpillar/Cummins know their stuff, unfortunately is not a very powerful or convincing debate tactic.
No, I am pretty well grounded in the real world. You know, physics and all that. You keep ignoring physics and other real world stuff like that. I think at this point, even die hard diesel fanatics are face-palming.
I don't see anyone pulling trailers with a john deer on the highway anymore than I see any big rigs screaming along at 12,000 RPM burning gasoline.
Horsepower is horsepower and that is how we rate the amount of work done over time. That is the real world and Caterpillar and Cummins understand that perfectly well.
โMar-18-2014 08:55 AM
goducks10 wrote:Thank you! Well put!!
High HP, low TQ for lighter vehicles.
High TQ, low HP for heavier vehicles.
Done.
โMar-18-2014 08:55 AM
โMar-18-2014 08:49 AM
โMar-18-2014 08:42 AM
OhhWell wrote:Those numbers are far from fictitious. There are many high performance, naturally aspirated engines in Europe and Japan that have similar HP/torque numbers.otrfun wrote:I'm sorry if the torque and horsepower numbers you came up with off of the top of your head require RPMs that are next to unheard of for the high horsepower option. I should have thought of that but just took it at face value. I guess you really got me! :R BUT, then again, it was your fictitious engie so therefore, it must be able to rev that high since you classified it as a 400HP engine! I guess you didn't actually get me.OhhWell wrote:I totally and respectfully disagree. Please reread my previous posts referencing HP = Torque x RPM /5252. Using this formula, please explain why you would choose a 400 HP, 200 ft. lb. of torque engine that has to rev over 10,000 RPM as a practical truck engine. Until you address this, then I don't believe you have a credible argument.otrfun wrote:I do not have horsepower and torque confused. I was wondering if perhaps you did? Torque doesn't pull ANYTHING is it a measure of force. It is a very important measurement but doesn't have squat to do with acceleration or top speed. If these high torque diesel engines could rev as high as gassers do, they would have insane amounts of horsepower.OhhWell wrote:You're jokin', right?! If not, is it possible you have horsepower and torque confused? There's a reason why diesel engines are so popular--it's NOT because they have horsepower--it's because they have TORQUE. Again, torque pulls the trailers, hauls the goods, does the work in the realworld. If horsepower was doing all these great things why don't we see Indy 500-type engines powering big trucks? They're small, lightweight, and they produce 700+ horsepower. There's a reason why you'll never see one in a big truck--it's because they have very little torque.otrfun wrote:I would pick engine 1 any day of the week. I might actually have to climb a hill at some point. I'm assuming that in this scenario, the same exact transmission isn't forced on both engines?OhhWell wrote:I get your technical point; however, I believe you missed my point.otrfun wrote:Who in the heck says that? Torque is a measure of force and horsepower is a measure of WORK.
As they say, torque does the real work, not horsepower.
You can multiply torque through gearing. You can't increase your horsepower through anything besides upgrading the powerplant.
Definition of horsepower
It's just a case of semantics. Notice my use of the word "real" work. I'm talking about work as defined by the average person:
"activity involving physical effort done in order to achieve a purpose or result"
If someone needs to haul or tow a lot, and wants to "achieve a purpose or result", which engine would be the better choice?
1. An engine with 400 HP and 200 ft. lbs. of torque.
2. An engine with 200 HP and 400 ft. lbs. of torque.
I think most would choose engine #2. Why? Because in the above scenario an abundance of torque allows them to "work" at "achieving a purpose or result" much easier than an abundance of horsepower.
P.S. I see your point about gearing down to increase torque. However, if this was an efficient process, can you explain why we don't see 700+ horsepower Indy 500-type engines powering big trucks?
The reason you don't see Indy Car engines in big trucks is due to longevity and fuel economy. Big trucks and diesel engine manufacturers don't spout out Torque numbers except (it appears) to the light duty truck consumers. Even there we are starting to see a horsepower push and race. Top speed calculations don't take torque into consideration at all, incline or not, it is all horsepower.
Luckily, diesel engines these days have more than enough horsepower as well so it's really all good. Your scenario you posed was too extreme. I wouldn't want to tow a heavy load up a decent hill with only 200hp no matter what the fuel type. You can scream TORQUE all you want but it isn't going to go very fast.
I could see maybe bringing it to 7k RPM or so however because that is not unheard of for a gas engine and I'm still going to go faster up the hill than with the 200 HP dog.
I don't think it makes your odd position that torque is everything any more valid unfortunately. I have driven High torque, low horsepower engine equipped vehicles before. Everything is well and good and the feeling of power is great until you get to a point and then.... well, there is nothing left. Horsepower is horsepower and only horsepower will determine how fast you are going to pull a load.
โMar-18-2014 08:02 AM
otrfun wrote:OhhWell wrote:I totally and respectfully disagree. Please reread my previous posts referencing HP = Torque x RPM /5252. Using this formula, please explain why you would choose a 400 HP, 200 ft. lb. of torque engine that has to rev over 10,000 RPM as a practical truck engine. Until you address this, then I don't believe you have a credible argument.otrfun wrote:I do not have horsepower and torque confused. I was wondering if perhaps you did? Torque doesn't pull ANYTHING is it a measure of force. It is a very important measurement but doesn't have squat to do with acceleration or top speed. If these high torque diesel engines could rev as high as gassers do, they would have insane amounts of horsepower.OhhWell wrote:You're jokin', right?! If not, is it possible you have horsepower and torque confused? There's a reason why diesel engines are so popular--it's NOT because they have horsepower--it's because they have TORQUE. Again, torque pulls the trailers, hauls the goods, does the work in the realworld. If horsepower was doing all these great things why don't we see Indy 500-type engines powering big trucks? They're small, lightweight, and they produce 700+ horsepower. There's a reason why you'll never see one in a big truck--it's because they have very little torque.otrfun wrote:I would pick engine 1 any day of the week. I might actually have to climb a hill at some point. I'm assuming that in this scenario, the same exact transmission isn't forced on both engines?OhhWell wrote:I get your technical point; however, I believe you missed my point.otrfun wrote:Who in the heck says that? Torque is a measure of force and horsepower is a measure of WORK.
As they say, torque does the real work, not horsepower.
You can multiply torque through gearing. You can't increase your horsepower through anything besides upgrading the powerplant.
Definition of horsepower
It's just a case of semantics. Notice my use of the word "real" work. I'm talking about work as defined by the average person:
"activity involving physical effort done in order to achieve a purpose or result"
If someone needs to haul or tow a lot, and wants to "achieve a purpose or result", which engine would be the better choice?
1. An engine with 400 HP and 200 ft. lbs. of torque.
2. An engine with 200 HP and 400 ft. lbs. of torque.
I think most would choose engine #2. Why? Because in the above scenario an abundance of torque allows them to "work" at "achieving a purpose or result" much easier than an abundance of horsepower.
P.S. I see your point about gearing down to increase torque. However, if this was an efficient process, can you explain why we don't see 700+ horsepower Indy 500-type engines powering big trucks?
The reason you don't see Indy Car engines in big trucks is due to longevity and fuel economy. Big trucks and diesel engine manufacturers don't spout out Torque numbers except (it appears) to the light duty truck consumers. Even there we are starting to see a horsepower push and race. Top speed calculations don't take torque into consideration at all, incline or not, it is all horsepower.
Luckily, diesel engines these days have more than enough horsepower as well so it's really all good. Your scenario you posed was too extreme. I wouldn't want to tow a heavy load up a decent hill with only 200hp no matter what the fuel type. You can scream TORQUE all you want but it isn't going to go very fast.
โMar-18-2014 07:49 AM
OhhWell wrote:I totally and respectfully disagree. Please reread my previous posts referencing HP = Torque x RPM /5252. Using this formula, please explain why you would choose a 400 HP, 200 ft. lb. of torque engine that has to rev over 10,000 RPM as a practical truck engine. Until you address this, then I don't believe you have a credible argument.otrfun wrote:I do not have horsepower and torque confused. I was wondering if perhaps you did? Torque doesn't pull ANYTHING is it a measure of force. It is a very important measurement but doesn't have squat to do with acceleration or top speed. If these high torque diesel engines could rev as high as gassers do, they would have insane amounts of horsepower.OhhWell wrote:You're jokin', right?! If not, is it possible you have horsepower and torque confused? There's a reason why diesel engines are so popular--it's NOT because they have horsepower--it's because they have TORQUE. Again, torque pulls the trailers, hauls the goods, does the work in the realworld. If horsepower was doing all these great things why don't we see Indy 500-type engines powering big trucks? They're small, lightweight, and they produce 700+ horsepower. There's a reason why you'll never see one in a big truck--it's because they have very little torque.otrfun wrote:I would pick engine 1 any day of the week. I might actually have to climb a hill at some point. I'm assuming that in this scenario, the same exact transmission isn't forced on both engines?OhhWell wrote:I get your technical point; however, I believe you missed my point.otrfun wrote:Who in the heck says that? Torque is a measure of force and horsepower is a measure of WORK.
As they say, torque does the real work, not horsepower.
You can multiply torque through gearing. You can't increase your horsepower through anything besides upgrading the powerplant.
Definition of horsepower
It's just a case of semantics. Notice my use of the word "real" work. I'm talking about work as defined by the average person:
"activity involving physical effort done in order to achieve a purpose or result"
If someone needs to haul or tow a lot, and wants to "achieve a purpose or result", which engine would be the better choice?
1. An engine with 400 HP and 200 ft. lbs. of torque.
2. An engine with 200 HP and 400 ft. lbs. of torque.
I think most would choose engine #2. Why? Because in the above scenario an abundance of torque allows them to "work" at "achieving a purpose or result" much easier than an abundance of horsepower.
P.S. I see your point about gearing down to increase torque. However, if this was an efficient process, can you explain why we don't see 700+ horsepower Indy 500-type engines powering big trucks?
The reason you don't see Indy Car engines in big trucks is due to longevity and fuel economy. Big trucks and diesel engine manufacturers don't spout out Torque numbers except (it appears) to the light duty truck consumers. Even there we are starting to see a horsepower push and race. Top speed calculations don't take torque into consideration at all, incline or not, it is all horsepower.
Luckily, diesel engines these days have more than enough horsepower as well so it's really all good. Your scenario you posed was too extreme. I wouldn't want to tow a heavy load up a decent hill with only 200hp no matter what the fuel type. You can scream TORQUE all you want but it isn't going to go very fast.
โMar-18-2014 07:16 AM
otrfun wrote:OhhWell wrote:You're jokin', right?! If not, is it possible you have horsepower and torque confused? There's a reason why diesel engines are so popular--it's NOT because they have horsepower--it's because they have TORQUE. Again, torque pulls the trailers, hauls the goods, does the work in the realworld. If horsepower was doing all these great things why don't we see Indy 500-type engines powering big trucks? They're small, lightweight, and they produce 700+ horsepower. There's a reason why you'll never see one in a big truck--it's because they have very little torque.otrfun wrote:I would pick engine 1 any day of the week. I might actually have to climb a hill at some point. I'm assuming that in this scenario, the same exact transmission isn't forced on both engines?OhhWell wrote:I get your technical point; however, I believe you missed my point.otrfun wrote:Who in the heck says that? Torque is a measure of force and horsepower is a measure of WORK.
As they say, torque does the real work, not horsepower.
You can multiply torque through gearing. You can't increase your horsepower through anything besides upgrading the powerplant.
Definition of horsepower
It's just a case of semantics. Notice my use of the word "real" work. I'm talking about work as defined by the average person:
"activity involving physical effort done in order to achieve a purpose or result"
If someone needs to haul or tow a lot, and wants to "achieve a purpose or result", which engine would be the better choice?
1. An engine with 400 HP and 200 ft. lbs. of torque.
2. An engine with 200 HP and 400 ft. lbs. of torque.
I think most would choose engine #2. Why? Because in the above scenario an abundance of torque allows them to "work" at "achieving a purpose or result" much easier than an abundance of horsepower.
P.S. I see your point about gearing down to increase torque. However, if this was an efficient process, can you explain why we don't see 700+ horsepower Indy 500-type engines powering big trucks?
โMar-17-2014 11:17 PM
B3yond Iris wrote:Yup, engines have come a long way in the last 10-20 years. It's amazing how engineers have been able to increase HP and torque and decrease fuel consumption at the same time. I agree, it's almost like we can have our cake and eat it, too ๐otrfun wrote:Thank you for explaining that. But thankfully with the way the engines have been able to produce their power its getting closer to the point where people can have their cake and eat it too.B3yond Iris wrote:The formula is just a general guideline. There are mass, friction, and combustion issues that enter into the overall design of an engine that are not reflected in this formula.otrfun wrote:I'm not sure how that HP=Torque X RPM/5252 came into play,but I personally have never seen it come true for any engine
Ok, time to refocus things. HP is a product of Torque and RPM (HP = TORQUE X RPM / 5252).
Take the 6.2L GM engine with
420HP @5600RPM
460 Torque @4100RPM
Following that formula it would be as following
HP=(460*4100)/5252 Which equals 359.101
FWIW, I could be mistaken, but I believe this formula calculates the torque being produced at the same RPM when maximum HP is being produced. Using the numbers you provided (and this formula), 394 ft. lbs. of torque are being produced at the same time 420 HP is being produced at 5600 RPM.
The general point I'm trying to make (with this formula) is that there is a give and take in terms of HP, Torque, and RPM. Some seem to think that HP is the cat's meow all by itself--that an engine with tons of HP will some how perform better under all conditions without any regard to its torque characteristics--that is simply not true. Again, HP is the product of Torque and RPM. Change one variable, and the other one or two variables must change, too.
โMar-17-2014 10:58 PM
otrfun wrote:B3yond Iris wrote:The formula is just a general guideline. There are mass, friction, and combustion issues that enter into the overall design of an engine that are not reflected in this formula.otrfun wrote:I'm not sure how that HP=Torque X RPM/5252 came into play,but I personally have never seen it come true for any engine
Ok, time to refocus things. HP is a product of Torque and RPM (HP = TORQUE X RPM / 5252).
Take the 6.2L GM engine with
420HP @5600RPM
460 Torque @4100RPM
Following that formula it would be as following
HP=(460*4100)/5252 Which equals 359.101
FWIW, I could be mistaken, but I believe this formula calculates the torque being produced at the same RPM when maximum HP is being produced. Using the numbers you provided (and this formula), 394 ft. lbs. of torque are being produced at the same time 420 HP is being produced at 5600 RPM.
The general point I'm trying to make (with this formula) is that there is a give and take in terms of HP, Torque, and RPM. Some seem to think that HP is the cat's meow all by itself--that an engine with tons of HP will some how perform better under all conditions without any regard to its torque characteristics--that is simply not true. Again, HP is the product of Torque and RPM. Change one variable, and the other one or two variables must change, too.
โMar-17-2014 10:54 PM
B3yond Iris wrote:The formula is just a general guideline. There are mass, friction, and combustion issues that enter into the overall design of an engine that are not reflected in this formula.otrfun wrote:I'm not sure how that HP=Torque X RPM/5252 came into play,but I personally have never seen it come true for any engine
Ok, time to refocus things. HP is a product of Torque and RPM (HP = TORQUE X RPM / 5252).
Take the 6.2L GM engine with
420HP @5600RPM
460 Torque @4100RPM
Following that formula it would be as following
HP=(460*4100)/5252 Which equals 359.101
โMar-17-2014 10:22 PM
otrfun wrote:
Ok, time to refocus things. HP is a product of Torque and RPM (HP = TORQUE X RPM / 5252).
โMar-17-2014 09:44 PM
โMar-17-2014 07:52 PM
Jarlaxle wrote:Physics in junior high school?! Maybe back in the 50's and 60's. Very rare these days.
By that logic, tow with a Poppin' Johnny. LOTS of torque...but little POWER!
Repeat after me: one horsepower equals one horsepower! This is junior high school physics!
โMar-17-2014 05:04 PM