v10 torque vrs diesel

[tres_perros]

Hello folks

I have been looking for a used class A leaning towards a diesel as I plan on towing a Jeep and travel west coast, rockies

Evidentially I am told that the newer V10 fords have very similar torque range ( a model change with an extra valve)

So Id love to hear some opinions regarding this, including if maintenance/warranty contracts are any cheaper...

Thanks ahead of time! This is a great forum and has been very helpful

Keith

[Cloud_Dancer]

uncleluap wrote:
we can banter back and forth till the cows come home,use 5252X whatever
Use whatever formula u were taught.I have no knowledge of such stuff
I absolutely know one thing for sure.There is not a V8 or V10 in production today that come,s even close to being able to feasable propel a 40+Ft 4 slide 34K motorhome down the road and up mountain passes and if there was we would be seeing them.thats why we only see engines like the 425 8.9L cummins doing the job and not ford V10.thats my opinion

Well yeah, but they don't want to discuss the real world of selecting/buying a motorhome. They want to simply quote the horsepower formula, and then repeat it several times for good measure,......as if it's more than we can understand.
What nobody seems to understand is that the manufacturers use a gasoline engine if it's appropriate, and the same for a diesel.

[uncleluap]

we can banter back and forth till the cows come home,use 5252X whatever
Use whatever formula u were taught.I have no knowledge of such stuff
I absolutely know one thing for sure.There is not a V8 or V10 in production today that come,s even close to being able to feasable propel a 40+Ft 4 slide 34K motorhome down the road and up mountain passes and if there was we would be seeing them.thats why we only see engines like the 425 8.9L cummins doing the job and not ford V10.thats my opinion

[Cloud_Dancer]

uncleluap wrote:

Cloud Dancer wrote:
uncleluap,
Please explain this, because I don't believe it's the reason:

"......The reason you don't see gassers in bigger MH's is that the people with the money for a 40' MH are also willing to pay the money for an air-ride suspension system and to have the engine/transmission in the back (quieter)...."

sorry cant help you as i never posted that dribble? I laughed actually when i saw that as in my opinion thats not the reason.I think u mixed up my stuff with others perhaps/

427435 I absolutely disagree with your statement:
Again, it's not the torque but the hp (and enough gears) that actually move a MH uphill.
The reason you don't see gassers in bigger MH's is that the people with the money for a 40' MH are also willing to pay the money for an air-ride suspension system and to have the engine/transmission in the back (quieter).

first off air ride suspention has nothing to do with what we are discussing and as i alluded to earlier there just is not a gas engine avaialable that has the torque or durabilty to propel 40Ft+ 36k+ motorhomes down the road.
its been tryed before and failed miserable

-------------------------------------------------

This is how it appeared, WITHOUT quotation marks. That's the reason I mistook it for yours. Sorry

I trust 427435 will pick it up.

[uncleluap]

Cloud Dancer wrote:
uncleluap,
Please explain this, because I don't believe it's the reason:

"......The reason you don't see gassers in bigger MH's is that the people with the money for a 40' MH are also willing to pay the money for an air-ride suspension system and to have the engine/transmission in the back (quieter)...."

sorry cant help you as i never posted that dribble? I laughed actually when i saw that as in my opinion thats not the reason.I think u mixed up my stuff with others perhaps/

[Cloud_Dancer]

uncleluap,
Please explain this, because I don't believe it's the reason:

"......The reason you don't see gassers in bigger MH's is that the people with the money for a 40' MH are also willing to pay the money for an air-ride suspension system and to have the engine/transmission in the back (quieter)...."

[Javi1]

DanTheRVMan wrote:

Javi1 wrote:
Torque is a measure of the ability of an engine to do work. It's a component of, but not the same as, the horsepower of the engine, which is the rate at which work can be done. In an automotive engine, power and torque are related by a simple equation that considers torque, engine speed (in revolutions per minute), and a conversion factor of 5252
Torque x RPM / 5252
In this equation, torque is expressed in terms of ft-lbs, the engine speed is given in revolutions per minute, and 5252 is a conversion constant. An engine's horsepower, then, isn't constant, but rather varies with its speed.
Here’s the problem with horsepower... it is the potential or speed at which work can be done while torque is the ability to work....
While it is possible to take two 350 hp engines and make the same speed pulling the same load up an incline the one with the most torque at the lowest rpm is going to get there cheaper and usually faster because the other will require more gear reduction to produce the same forward force... Which will result in higher rpm’s needed, more fuel burned and more heat produced of which requiring more cooling which adds weight which requires more power (torque) or decrease in payload..
An example is my 6.7 liter diesel which produces 400 HP at 2800 rpm but 800 ft-lbs of torque at 1600 rpm... using the above equation one can see that the 6.7 produces 800 x 1600 / 5252 = 243.72 hp at 1600 rpm, far from the potential peak hp of 400 at 2800 rpm... Although in looking at the torque curve of the 6.7 it is apparent that the 800 ft-lbs is nearly constant through the range of 1600 to 2800 giving the 6.7 a very high work range.
The Ford V-10 gas engine produced 457 ft-lbs of torque at 3250 and 362 hp at 4750 using the above equation one can see that the V-10 produced 457 X 3250 / 5252 = 282.79 hp a gain of 39.07 HP but at the cost of more than twice the revolutions... to produce slightly more than ½ the torque of the 6.7 diesel.
While the design of the gas V-10 is aimed at higher RPM the life expectancy of an engine turning at well over twice it’s normal operating range is almost certainly going to be reduced by some factor if one expects it to produce the same work ability through increased rpm.. and gearing..

You are right about the shape of a gas engines torgue curve, but gas engines are lighter not heavier than diesels.

Speed is determined by weight/hp and gas MHs are generally much lighter than diesels MHs so for the same HP a gas MH will be faster in spite of the worse shape of torque or hp curves.

As for the life of the engines you are correct the diesel should last lots longer. But since gas will last over 100k and most people wear out the house first this is not a good reason for many people to blow their budget and buy a diesel so the fourth owner can go a few more miles.

Yes, generally a gas engine is found in a smaller coach, however the original question was (I think) about the same size coach just gas or diesel powered.. in which case unless it was one of the smaller coaches.. the diesel will win, especially if you base winning on longivity X power / fuel expense.

[uncleluap]

Jarlaxle wrote:

uncleluap wrote:
427435 I absolutely disagree with your statement:
Again, it's not the torque but the hp (and enough gears) that actually move a MH uphill.
The reason you don't see gassers in bigger MH's is that the people with the money for a 40' MH are also willing to pay the money for an air-ride suspension system and to have the engine/transmission in the back (quieter).

first off air ride suspention has nothing to do with what we are discussing and as i alluded to earlier there just is not a gas engine avaialable that has the torque or durabilty to propel 40Ft+ 36k+ motorhomes down the road.
its been tryed before and failed miserable

This post can only be called a LIE.

why is it a lie? I thought it was called an opinion of whats being discussed ? You will never see nor have you ever seen a 40ft+ 4 slide 34+K motorhome powered by a 400 lb torque v8 or V10
If you disagree so be it but dont be calling people liers just because u simple disagree with their ideals(opinion)

[DanTheRVMan]

Javi1 wrote:
Torque is a measure of the ability of an engine to do work. It's a component of, but not the same as, the horsepower of the engine, which is the rate at which work can be done. In an automotive engine, power and torque are related by a simple equation that considers torque, engine speed (in revolutions per minute), and a conversion factor of 5252
Torque x RPM / 5252
In this equation, torque is expressed in terms of ft-lbs, the engine speed is given in revolutions per minute, and 5252 is a conversion constant. An engine's horsepower, then, isn't constant, but rather varies with its speed.
Here’s the problem with horsepower... it is the potential or speed at which work can be done while torque is the ability to work....
While it is possible to take two 350 hp engines and make the same speed pulling the same load up an incline the one with the most torque at the lowest rpm is going to get there cheaper and usually faster because the other will require more gear reduction to produce the same forward force... Which will result in higher rpm’s needed, more fuel burned and more heat produced of which requiring more cooling which adds weight which requires more power (torque) or decrease in payload..
An example is my 6.7 liter diesel which produces 400 HP at 2800 rpm but 800 ft-lbs of torque at 1600 rpm... using the above equation one can see that the 6.7 produces 800 x 1600 / 5252 = 243.72 hp at 1600 rpm, far from the potential peak hp of 400 at 2800 rpm... Although in looking at the torque curve of the 6.7 it is apparent that the 800 ft-lbs is nearly constant through the range of 1600 to 2800 giving the 6.7 a very high work range.
The Ford V-10 gas engine produced 457 ft-lbs of torque at 3250 and 362 hp at 4750 using the above equation one can see that the V-10 produced 457 X 3250 / 5252 = 282.79 hp a gain of 39.07 HP but at the cost of more than twice the revolutions... to produce slightly more than ½ the torque of the 6.7 diesel.
While the design of the gas V-10 is aimed at higher RPM the life expectancy of an engine turning at well over twice it’s normal operating range is almost certainly going to be reduced by some factor if one expects it to produce the same work ability through increased rpm.. and gearing..

You are right about the shape of a gas engines torgue curve, but gas engines are lighter not heavier than diesels.

Speed is determined by weight/hp and gas MHs are generally much lighter than diesels MHs so for the same HP a gas MH will be faster in spite of the worse shape of torque or hp curves.

As for the life of the engines you are correct the diesel should last lots longer. But since gas will last over 100k and most people wear out the house first this is not a good reason for many people to blow their budget and buy a diesel so the fourth owner can go a few more miles.

[Javi1]

Torque is a measure of the ability of an engine to do work. It's a component of, but not the same as, the horsepower of the engine, which is the rate at which work can be done. In an automotive engine, power and torque are related by a simple equation that considers torque, engine speed (in revolutions per minute), and a conversion factor of 5252

Torque x RPM / 5252

In this equation, torque is expressed in terms of ft-lbs, the engine speed is given in revolutions per minute, and 5252 is a conversion constant. An engine's horsepower, then, isn't constant, but rather varies with its speed.

Here’s the problem with horsepower... it is the potential or speed at which work can be done while torque is the ability to work....

While it is possible to take two 350 hp engines and make the same speed pulling the same load up an incline the one with the most torque at the lowest rpm is going to get there cheaper and usually faster because the other will require more gear reduction to produce the same forward force... Which will result in higher rpm’s needed, more fuel burned and more heat produced of which requiring more cooling which adds weight which requires more power (torque) or decrease in payload..

An example is my 6.7 liter diesel which produces 400 HP at 2800 rpm but 800 ft-lbs of torque at 1600 rpm... using the above equation one can see that the 6.7 produces 800 x 1600 / 5252 = 243.72 hp at 1600 rpm, far from the potential peak hp of 400 at 2800 rpm... Although in looking at the torque curve of the 6.7 it is apparent that the 800 ft-lbs is nearly constant through the range of 1600 to 2800 giving the 6.7 a very high work range.

The Ford V-10 gas engine produced 457 ft-lbs of torque at 3250 and 362 hp at 4750 using the above equation one can see that the V-10 produced 457 X 3250 / 5252 = 282.79 hp a gain of 39.07 HP but at the cost of more than twice the revolutions... to produce slightly more than ½ the torque of the 6.7 diesel.

While the design of the gas V-10 is aimed at higher RPM the life expectancy of an engine turning at well over twice it’s normal operating range is almost certainly going to be reduced by some factor if one expects it to produce the same work ability through increased rpm.. and gearing..

[Cloud_Dancer]

Neither side is going to win this argument until you race uphill a 36,000 lb production gas motorhome against a 36,000 lb diesel motorhome. Of course, this isn't going to happen either.
So, you have no choice. Each one of us is going to believe what we believe, and hopefully we can go forward and enjoy whatever motorhome we might choose.
Me? I don't care what you believe. I'm totally convinced that I chose wisely.
Pride of ownership of Turbo Cummins engine that specs out at 1,050 lbs/ft torque at a low RPM, with smart Allison 6 speed, and side radiator powered by multi-speed hydraulic motor,....THAT'S what it's all about! Check out the smile:

[jmtandem]

Actually, they will. I have seen it firsthand: we had two 275HP semi tractors at work...one made it at ~2300RPM with a little C7, the other at ~1700RPM with a big C10. Hauling the same weight, they would climb hills at EXACTLY THE SAME SPEED. The smaller engine just had to run higher RPM's...it was no problem, as it was geared accordingly.

[427435]

Horse Power equals Torgue (ft-lbs) times RPM divided by 5252. There is no diesel or gas in the equation.

For those of you that don't want to believe a 350 gas engine with 400 ft-lbs torque won't pull a 36,000 lb vehicle up a hill, please explain how a gas turbine putting out much less torque moves a heavy battle tank up steep inclines!!

[jmtandem]

Not a theory...a simple fact. It's basic physics: 350HP is 350HP.

[Cloud_Dancer]

OK I'll play the word game.
With regard to this discussion, torque that is being applied but not doing any work is nothing/worthless. But, that's really not the torque that is being discussed. The torque that is being discussed is continuous, which means it can be used to do work. At this point, it IS the torque that is doing the work. The horsepower formula comes later, in event that you choose to quantify the torque 'on paper'. And, that's the reason that people say it's the horsepower that does the work.

[Jarlaxle]

uncleluap wrote:

427435 wrote:
Many of you are confusing force (torque) with power and work (hp) and need to re-take physics 101. Torque is the force on the axle TRYING to turn it. There can be a lot of torque on that axle BUT, if it is not turning, there is no movement of the MH and no WORK being done. When it is turning, there is WORK being done. The faster the axle turns, the more work (hp) is being done. Remember that a 1000 hp gas turbine may only have 175 ft-lbs maximum torque, but it is spinning at 30,000 rpm. And it will move a tank nicely and last a long time.

A 350 hp gas engine will do as much WORK as a 350 hp diesel engine. It may not last as long operating at max hp as a diesel engine, but that is due to design targets the engineers were given. The gas engine will also need more gear reduction to keep it in its peak hp rpm range.

so then in theory your claiming a 350 HP gas engine will power the
the 34000lb MH up a hill at the same rate and speed as the 350HP cimmins will? just operating at different RPM ratings?gas being 3X what the diesel is reving

Not a theory...a simple fact. It's basic physics: 350HP is 350HP.