5 ms·

40 liters per 100 KM = 10gal/60mi. It's about 6mpg. Not great, not as bad as I would have guessed.

by blhack 12y ago

foobarian 12y ago
Surprising that a 5.5 liter engine has only 140 horsepower. Goes to show just how far modern engine design has come.
- justin66 12y ago
  The 6.2 liter, normally aspirated diesel engine that powered old Suburbans as well as the military HMMWV made about that, even with its greater displacement. Even the modern turbo diesel HMMWV doesn't break 200hp, according to Wikipedia. Torque, reliability, serviceability and maximizing defense contractor profits probably rank as much higher priorities for the military than pure horsepower.
- bigdubs 12y ago
  It's not 140 horsepower because it is designed poorly; that's a trade-off to make it react well to bullets and explosions and still run, also field serviceability.
  - scottlocklin 12y ago
    It's actually a fairly poor design; probably a 1950s era Chrysler design.
    - VLM 12y ago
      You and OP are not necessarily disagreeing. A pressurized cooling system is a liability on a battlefield unless its REALLY worth it. (I don't remember if a 50s chevvy has a pressurized cooling system... I'm guessing not)
      - jschwartzi 12y ago
        Many engines from that era were air/oil cooled.
- dntrkv 12y ago
  Horsepower isn't nearly as important as torque for a vehicle like this. If you look at even modern work trucks, they may have a 6-7L engine pushing only ~300hp or so but with like 700-800lb-ft of torque. But yes, engines have come a long way. I remember being amazed at 450lb-ft of torque on diesel work truck. The new Fords push something like 860lb-ft.
  - grogers 12y ago
    Big torque from an engine sounds impressive but in reality only power matters. You can always change gear ratios to get more torque, which means more force to the ground. Power determines how fast you will accelerate, how fast your top speed is, etc. It's all about conservation of energy.
    - bcohen5055 12y ago
      Efficiency is really the name of the game. Do you really want to have a massive 7L engine spinning at redline just to be able to reduce that down 1:10 for some good torque? I'd much rather just an engine with the RPM held at the "crossover" of the Torque/HP lines or working within an island of efficency

40 liters per 100 KM = 10gal/60mi. It's about 6mpg. Not great, not as bad as I would have guessed.

by blhack 12y ago

40 liters per 100 KM = 10gal/60mi. It's about 6mpg. Not great, not as bad as I would have guessed.

foobarian 12y ago

Surprising that a 5.5 liter engine has only 140 horsepower. Goes to show just how far modern engine design has come.

justin66 12y ago
The 6.2 liter, normally aspirated diesel engine that powered old Suburbans as well as the military HMMWV made about that, even with its greater displacement. Even the modern turbo diesel HMMWV doesn't break 200hp, according to Wikipedia. Torque, reliability, serviceability and maximizing defense contractor profits probably rank as much higher priorities for the military than pure horsepower.
bigdubs 12y ago
It's not 140 horsepower because it is designed poorly; that's a trade-off to make it react well to bullets and explosions and still run, also field serviceability.
- scottlocklin 12y ago
  It's actually a fairly poor design; probably a 1950s era Chrysler design.
  - VLM 12y ago
    You and OP are not necessarily disagreeing. A pressurized cooling system is a liability on a battlefield unless its REALLY worth it. (I don't remember if a 50s chevvy has a pressurized cooling system... I'm guessing not)
    - jschwartzi 12y ago
      Many engines from that era were air/oil cooled.
dntrkv 12y ago
Horsepower isn't nearly as important as torque for a vehicle like this. If you look at even modern work trucks, they may have a 6-7L engine pushing only ~300hp or so but with like 700-800lb-ft of torque. But yes, engines have come a long way. I remember being amazed at 450lb-ft of torque on diesel work truck. The new Fords push something like 860lb-ft.
- grogers 12y ago
  Big torque from an engine sounds impressive but in reality only power matters. You can always change gear ratios to get more torque, which means more force to the ground. Power determines how fast you will accelerate, how fast your top speed is, etc. It's all about conservation of energy.
  - bcohen5055 12y ago
    Efficiency is really the name of the game. Do you really want to have a massive 7L engine spinning at redline just to be able to reduce that down 1:10 for some good torque? I'd much rather just an engine with the RPM held at the "crossover" of the Torque/HP lines or working within an island of efficency