Big Three road tests

[BlackSilver]

Found this review on line, of the three heavy duty pickups.

[buddyIam]

I think one with a stroker. The other a thruster.

[Majja13]

buddyIam wrote:
I wonder what kinda thrust that hooker takes?

Is that with a Stroker in it?

[ForestGump]

BlackSilver wrote:
Wow! You guys act like somebody called your sister a hooker.

They're just stupid trucks, not a religion!

Sorry I posted the link.

😄 Cool indeed

[DirtyOil]

When they remove the human factor from these tests then we'll really have something to chat about. Install some servos... cab and exterior sound recorders, motion sensors... etc. etc. then compare the results. Most of us will buy based on price, options, comfort, style and colour, some will buy based solely on advertising.

[mich800]

Huntindog wrote:

FishOnOne wrote:

Huntindog wrote:
Ever wonder how GM arrived at 397 HP?

And how Ford always has nice round even numbers?

Simple, and has been proven before.

GM tested the Dmax for reliability and power, then dynoed it to SAE standards to see just how much power it makes.

Ford wanted a nice round number that would exceed the Dmax. So they tuned for a number on the dyno, but not to SAE standards.

Think about the difference between peak HP, and continuous HP.

The Ford can indeed make the advertised HP/TQ for a short time. Then the computer dials back the power to keep it from hurting itself.

The GM can make their lower HP/TQ much longer. Long enough to meet the SAE standards, and likely continuously.

So in effect the GM wins on the road,,, time after time.

I disagree... The last Ford power curves I've seen on the 6.7 PSD looked pretty darn flat to me.

Fish, I expected that you would disagree.

But it is a FACT that the GM is the only one doing dyno testing to SAE standards.

The documentation has been posted here before. I know you have seen it.
Power curves are not what I am talking about.

And you cannot deny that the Ford numbers are ALWAYS nice round numbers, that just happen to be higher than GMs.

I remember a GM engineer being asked about why they came up with 397 HP, when a nice round 400 could have been achieved. His response was to the effect of:: We have done a lot of testing with the Dmax. 397 is what the number came in at, and we are comfortable and confident with that number.

There are really only two choices anyways. Since GM has consistently spanked the Ford in many tests, either the Ford is over rated, or the GM is under rated.
It would make little sense to under rate a truck, as that will cost sales.
But if you get a higher rating by any means possible, including loose testing standards, then you can advertise that rating, and many will believe it.

I have not seen the articles you are speaking of. But there is far more to timed tests than just HP. Trans gear ratios and efficiency, wheel and tire weight, aerodynamics, total vehicle weight, torque limiting off the line just to name a few. I am not saying you are wrong but if hp was the end all of these tests than every vehicle with the same hp car, truck, moped would have exactly the same elapsed time.

[Huntindog]

FishOnOne wrote:

Huntindog wrote:
Ever wonder how GM arrived at 397 HP?

And how Ford always has nice round even numbers?

Simple, and has been proven before.

GM tested the Dmax for reliability and power, then dynoed it to SAE standards to see just how much power it makes.

Ford wanted a nice round number that would exceed the Dmax. So they tuned for a number on the dyno, but not to SAE standards.

Think about the difference between peak HP, and continuous HP.

The Ford can indeed make the advertised HP/TQ for a short time. Then the computer dials back the power to keep it from hurting itself.

The GM can make their lower HP/TQ much longer. Long enough to meet the SAE standards, and likely continuously.

So in effect the GM wins on the road,,, time after time.

I disagree... The last Ford power curves I've seen on the 6.7 PSD looked pretty darn flat to me.

Fish, I expected that you would disagree.

But it is a FACT that the GM is the only one doing dyno testing to SAE standards.

The documentation has been posted here before. I know you have seen it.
Power curves are not what I am talking about.

And you cannot deny that the Ford numbers are ALWAYS nice round numbers, that just happen to be higher than GMs.

I remember a GM engineer being asked about why they came up with 397 HP, when a nice round 400 could have been achieved. His response was to the effect of:: We have done a lot of testing with the Dmax. 397 is what the number came in at, and we are comfortable and confident with that number.

There are really only two choices anyways. Since GM has consistently spanked the Ford in many tests, either the Ford is over rated, or the GM is under rated.
It would make little sense to under rate a truck, as that will cost sales.
But if you get a higher rating by any means possible, including loose testing standards, then you can advertise that rating, and many will believe it.

[hone_eagle]

A lot of 'transmission protection' goes on these days of big tork engine output.

[FishOnOne]

Huntindog wrote:
Ever wonder how GM arrived at 397 HP?

And how Ford always has nice round even numbers?

Simple, and has been proven before.

GM tested the Dmax for reliability and power, then dynoed it to SAE standards to see just how much power it makes.

Ford wanted a nice round number that would exceed the Dmax. So they tuned for a number on the dyno, but not to SAE standards.

Think about the difference between peak HP, and continuous HP.

The Ford can indeed make the advertised HP/TQ for a short time. Then the computer dials back the power to keep it from hurting itself.

The GM can make their lower HP/TQ much longer. Long enough to meet the SAE standards, and likely continuously.

So in effect the GM wins on the road,,, time after time.

I disagree... The last Ford power curves I've seen on the 6.7 PSD looked pretty darn flat to me.

[john_bet]

blt2ski wrote:

john&bet wrote:
Boy, I am glad you guys that are in such a big hurry don't drive behind the '13 28k+ school bus that I drive daily. With only 250hp and a 2500 rev limit and a 5 speed Allison it takes over 1500' to get it up to 55 mph on flat ground.

Or the 1992 IHC dump truck I have, with a 175/335 NA 7.3 diesel with a 7 speed spicer. Helps that I have 4.33 gears, 32" tires, and a 10.08-1 first gear to get going at 26k lbs too! Altho I can get 30k lbs to move up a 30% grade, sloooooooooooowly that is!

Marty

I know what you mean. I live on the same county road as a stone quarry and an asphalt plant. The dump trucks enter the same hi-way I do. I also deal with a lot of semi's on US-50. My buss has a DT-466.

[buddyIam]

Huntindog

I sure wish some of these testers would put these trucks on a dyno instead of quarter mile track.

How far would the Ford have to go before the computer would roll back the power.

A quarter mile sure seems like a short time for the power to be cut back. But the ford most definitely got it's butt handed to it.

Now that I think of it, on a normal dyno run the full power is only held for much less than a minute.

[Huntindog]

Ever wonder how GM arrived at 397 HP?

And how Ford always has nice round even numbers?

Simple, and has been proven before.

GM tested the Dmax for reliability and power, then dynoed it to SAE standards to see just how much power it makes.

Ford wanted a nice round number that would exceed the Dmax. So they tuned for a number on the dyno, but not to SAE standards.

Think about the difference between peak HP, and continuous HP.

The Ford can indeed make the advertised HP/TQ for a short time. Then the computer dials back the power to keep it from hurting itself.

The GM can make their lower HP/TQ much longer. Long enough to meet the SAE standards, and likely continuously.

So in effect the GM wins on the road,,, time after time.

[buddyIam]

I wonder what kinda thrust that hooker takes?

[DirtyOil]

Sport45 wrote:


buddyIam wrote:

Sports 45,

You made my point. You said it very well.

We should be concerned with power. Not horse power.

Horse power is an approximation.

It is based on torque and speed/distance. That is power that can be scientifically measured.

You don't need hp or power to have torque. But you must have torque to have power or hp.

Hp=rpm×torque/5252. The formula says it all. If there is zero rpm. Torque can be 1 million and hp would still be zero.

If hp is any number greater than zero. Then neither torque nor rpm can be zero.


Torque and rpm are the determining factors. Not hp. Hp is not a measurement it is an approximation dreamed up to sell stream engines.


Now I understand. You want to live in your own little world where you compare power by looking at a torque curve and multiplying torque and rpm. That works. The rest of us just use the HP curve where the calculations have already been made.

But I bet if you compare the power levels of two engines in your world you'll find the one that has 20% more power also has 20% more power in our world. Doesn't matter if you use horsepower (which you seem to dislike), elephant power, or kilowatts.

Big diddily do... my truck produces 1982lbs of thrust!!! Beat that!! (horse power advocates.... that's POUNDS OF THRUST)
:B

[4x4ord]

Sport45 wrote:

buddyIam wrote:
Sports 45,

You made my point. You said it very well.

We should be concerned with power. Not horse power.

Horse power is an approximation.

It is based on torque and speed/distance. That is power that can be scientifically measured.

You don't need hp or power to have torque. But you must have torque to have power or hp.

Hp=rpm×torque/5252. The formula says it all. If there is zero rpm. Torque can be 1 million and hp would still be zero.

If hp is any number greater than zero. Then neither torque nor rpm can be zero.


Torque and rpm are the determining factors. Not hp. Hp is not a measurement it is an approximation dreamed up to sell stream engines.

Now I understand. You want to live in your own little world where you compare power by looking at a torque curve and multiplying torque and rpm. That works. The rest of us just use the HP curve where the calculations have already been made. 🙂

But I bet if you compare the power levels of two engines in your world you'll find the one that has 20% more power also has 20% more power in our world. Doesn't matter if you use horsepower (which you seem to dislike), elephant power, or kilowatts.

When a big RV is going down the level highway at 70 mph it is mainly the wind resistance on the vehicle that is defining the amount of torque necessary on the rear axle to maintain the vehicle speed. Slow down a bit and the torque requirement drops significantly.

When that heavy truck and trailer hit the big twisty hills things are a little different. You will likely be traveling a little slower and wind resistance is not playing nearly as big of role. The incline angle of the hill largely determines the amount of torque on the rear axle to maintain speed. If the engine isn't able to produce the necessary torque the truck slows down. Even though slowing down reduces the power required to maintain speed it makes little difference to the torque requirement which is largely being determined by the incline not wind resistance. So if the engine's torque curve is flat or falling off as the rpms drop the truck will rapidly slow down till a downshifting occurs. With this truck it is the transmission that is responsible for the torque increase. An engine (such as the Cummins) which has a significant torque rise as the rpm drops will have a higher tendency to pull the hill and downshifting will not be as often required. All this can be seen with a quick glance at an engine's torque curve.