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Topic: Weight vs Horsepower & Torque  (Read 991 times) previous topic - next topic

Weight vs Horsepower & Torque

Since I have always loved playing the number games, Thought maybe someone else might be interested in this little fact.

Example my 2001 U320, 36', 1 slide
30,000 lb coach with a 500 HP/1550ft lb = 60 lb per HP & 19.35 lb per FtLb.

Example 2010 Phenix 45' 4 slide
48,000 lb coach with a 650 HP/1950ft lb = 73 lb per HP & 24.61 lb per FtLb.

This does not take into account the rolling friction of a tag axle, tire size, not frontal area, nor any toad. Only based on weight and power.

Now there has to be an engineer who can calculate the difference in fuel burn if interested, I am not interested as it is all play, or who cares.

Re: Weight vs Horsepower & Torque

Reply #1 –
Dave,

Wonder how to figure in the width of the torque and hp curves that would effect real world performance? Seems as if cubic inches would lend itself to an empirical number factor. Torque curve maximum and width for 2 cycle vs. 4 cycle diesels for any given displacement?

Is that your Cessna 190-195?

Pierce & Gaylie
'93 U300/36

Pierce and Gaylie Stewart
'93 U300/36 WTBI
Detroit 6V-92TA Jake
1140 watts on the roof
SBFD (ret)

Re: Weight vs Horsepower & Torque

Reply #2 –
First off, the 195 275HP shakey Jake, No, never owned one, but always had a very warm fuzzy for those, still think the best looking bird ever to fly.  I only owned a PA28R-200 II, that is as fast as you can go cheap. True 143 kt.

As for the 2 vs 4 stroke, I always enjoyed the 12V-71 as a non turbo @ 520hp @2300rpm, the torque & hp are very close related, peak torque is at 1700 and hp at 2300, not being a turbo model, the massive torque from idle up is very awsome, why in the old days when that was used in a very few trucks, most has issues with driveline, U Joint, ring&Pinion failure due to the massive torque off idle.  The modern engines with turbo's can and will comeup with similar torque, however they have a delay in getting up to max torque due to "turbo lag", it sure saves a lot of drive line issues being a more gentle torque rise.
There are too many issues for me to calculate the overall, why my brother and I are planning on a real world expermint / spermint depending where you are from.  One thing, we actually get off mour butt and go play instead of talk our self to death, it provides real world experience / sperence.
We do not sit around a fire house reading paper backs being wannabee's.
The 12V in the MCI was very costly in $$, but maybe the single best period of my life playing with truckers, Charly Daniels, Fats Domino etc etc.....
Had the 12V up to about 780-800 hp with 2 turbos, more than a smile, with the turbo setup I retarded the timing to standard, and the torque curve lowered to about 1300 rpm. and lost the awsome torque from the non turbo settings, the overall was amazing. If you were involved with the CCO (Custom Coach Owners) group, most of those chaps have seen it, rode in it and took lots of pix.  Also had the RTO12510 RR with 3.73 rear, 11R24.5 tires.
Sorry for the long posting, but this  subject is where I live.  Not dreaming
Cheers

Re: Weight vs Horsepower & Torque

Reply #3 –
Dave M,

You mentioned "old days" of pulling max loads up mountains. My dad starting driving in 1960. My recollection is that his first truck was a Mack cabover with a Cummins 215 HP engine. It transmitted power through a quadriplex transmission with something like 18 usable forward speeds. It was straight six with no blower. Max weight then was about 77,000#. He made a lot of runs between OKC and California. He probably used all of those gears between OK and CA. On the one trip I got to make with him, I remember his putting an arm through the steering wheel and shifting both shift levers while syncing things up with the clutch and accelerator.

His last truck was a Peterbilt conventional with a CAT engine. He loved to drive all of his trucks except for the International Harvester. His favorite was the Peterbilt. I expect it had the best HP/Weight ratio of any of his trucks.
J D Stevens
1997 U295 CAI 36' Build #5085
2002 Subaru Outback
Motorcade 16869
Bellville, TX

Re: Weight vs Horsepower & Torque

Reply #4 –
J.D.  Yes, I started in 1970, drove about 2 years, all over USA, pulling a 40' reefer, Best truck was a Mack FS700L 318 DDA 13 speed 180: wheel base, manual steering, it had a super good ride, no power so you learned to row the 13 speed like an oar.  The mack had alot of aluminum and was light, about 13,500 lb.
The worst truck, I was given a new KW, 425 Cat C/O, toooo heavy 19.600lb, could not scale a load, fifth wheel too high, could not get on the Pa Turnpike, NYC, Phila, and most eastern cities were off limits doe to height issues, but it looked good, not a truck to make a living, so I got off the road and into emergency generators where I have been smiling ever since.
AS for the old quadraplex twin stick, yes thank god, I only drove one of them for 2 days, glad to get a ten speed road ranger.

Re: Weight vs Horsepower & Torque

Reply #5 –
It was warm today, so felt was a grand time to test the new power on the Afton Mtn on I-64, west bound, was able to accelerate slightly on the steepest part, when got above that area the speed went up nicely, so backed off to car passing happiness, was towing the F150 Ford. A large improvement and as mentioned before, feels like 200 hp upgrade, not 50 hp. Massive improvement.  It is now starting to run more like the MCI with the big DDA engine.
Now to change the TranSynd Allison synthetic and both filters in the 4060R and I will be ready for a nice trip.
The engine temp went  up slightly, but stayed below 200 during the hardest pull.
Was not after fuel mileage, but on return trip, got very cheerful mileage.
A lot to learn yet.
Cheers

Re: Weight vs Horsepower & Torque

Reply #6 –
Quote from: Dave M –
J.D.  Yes, I started in 1970, drove about 2 years, all over USA, pulling a 40' reefer, Best truck was a Mack FS700L 318 DDA 13 speed 180: wheel base, manual steering, it had a super good ride, no power so you learned to row the 13 speed like an oar.  The mack had alot of aluminum and was light, about 13,500 lb
Dave, I drove one of the exact same tractors too!  Was shortly after Vietnam.  Probably 1971 or 72.  Worster Motor Lines, North East, Pa.  Started driving in 1970.
1994 U225
build #4514

Re: Weight vs Horsepower & Torque

Reply #7 –
PatC, I have spent way too much time on mountains at 28 mph with a 318 & 13 spd, maybe why I see mountains as a challenge. WHo would not love a pair of 238's  ;D

Re: Weight vs Horsepower & Torque

Reply #8 –
Quote from: Dave M –
PatC, I have spent way too much time on mountains at 28 mph with a 318 & 13 spd, maybe why I see mountains as a challenge. WHo would not love a pair of 238's  ;D
Double breasted Yahamas, at least that is what my father in law called them.
1994 U225
build #4514