4 ms·

If you wanted to use an auto engine it would probably be a truck engine. Most car engines aren’t designed to be run at lets say 5,000rpms for an hour or so at a

by wil421 4y ago

If you wanted to use an auto engine it would probably be a truck engine. Most car engines aren’t designed to be run at lets say 5,000rpms for an hour or so at a time. It’s the same reason inboard/outboard engines in boats use big and small block GM designed truck engines (Merc and Volvo).

eru 4y ago
Yes. I was being a bit lax when I said 'car engine'. I basically meant any land transport engine with a large production run. (Though looking at ship engines might also be interesting. I assume they are heavier and bulkier than car or truck engines, but they probably can also run at high load for a long time? I don't know anything about them..)
- wil421 4y ago
  You wouldn’t want to run them wide open throttle for a long time but usually they give you a cruise RPM suggestion for optimal gas/speed. People make 20-30 miles runs offshore in smaller boats running them close to wide open for hours at a time. Yes I think they are heavier than their truck counterparts. Most are raw water cooled so they have intakes/risers and shoot water out the exhaust. The diesel ship engines are beasts, can take a beating, and run for 10x as many hours as a gas engine. It looks like they are too heavy for aircraft but there are some Diesel engine manufacturers listed on Wikipedia.
  - cardiffspaceman 4y ago
    Diesel engines on large ships typically work as diesel-electrics, the way railroad locomotives do. For example, Celebrity Solstice[1] uses diesel generators and azimuth thrust pods which contain electric motors. Celebrity Millennium[2] uses gas turbine generators and azimuth thrust pods. The electricity is also used for the rest of the electrical needs on the ship. The cruise industry is adopting LNG fuel, and hybrid power plants, gradually. [1] https://en.wikipedia.org/wiki/Celebrity_Solstice https://en.wikipedia.org/wiki/Celebrity_Solstice [2] https://en.wikipedia.org/wiki/Celebrity_Millennium https://en.wikipedia.org/wiki/Celebrity_Millennium
wolrah 4y ago
A truck engine is a great comparison point, because you can look at modern trucks for a perfect example of this. A Ford F-250 through F-450 pickup truck with the 6.7L "Power Stroke" diesel is rated for 475 HP and 1050 lb-ft of torque. The same engine in the same basic truck, but in commercial chassis-cab form, is rated for 330 HP and 825 lb-ft of torque. Step up to the medium duty F-650/750 chassis with a much larger cooling system and that engine is now rated for 270 HP and 700 lb-ft of torque, with optional software upgrades available for 300/725 or 330/750 configurations. The same applies to their gas motor, the pickup trucks get the 7.3L "Godzilla" engine with 430 HP and 475 lb-ft where the chassis-cabs and medium duty trucks get a 335 HP/468 lb-ft tune. The harder and more consistently the truck is expected to be worked the less power the engine is rated for. This isn't just a Ford thing either, GM and Ram also derate their commercial chassis compared to the pickups and the multiple power level thing on the medium duty diesels is common industry practice. Often the highest horsepower packages on larger diesels will be restricted to RV and/or emergency response applications where short bursts of power are more important than the ability to run hard for hours on end.
- sokoloff 4y ago
  As a point of reference to airplane engines, my first airplane made 230 HP @2700 RPM from 470 cubic inches (7.7 liters). My current airplane makes 325 HP @2700 RPM from 550 ci (9 liters).
  - hnuser123456 4y ago
    How fast does it go?
    - sokoloff 4y ago
      First was a Skylane (fixed gear, fairly draggy) and would do 135-140 knots on 12-ish gallons per hour. Second is an A36TN (retractable gear, turbo-normalized) and will do 185-ish knots (215-ish mph) on 15-16 gph.

by wil421 4y ago

eru 4y ago

Yes. I was being a bit lax when I said 'car engine'. I basically meant any land transport engine with a large production run. (Though looking at ship engines might also be interesting. I assume they are heavier and bulkier than car or truck engines, but they probably can also run at high load for a long time? I don't know anything about them..)

wil421 4y ago
You wouldn’t want to run them wide open throttle for a long time but usually they give you a cruise RPM suggestion for optimal gas/speed. People make 20-30 miles runs offshore in smaller boats running them close to wide open for hours at a time. Yes I think they are heavier than their truck counterparts. Most are raw water cooled so they have intakes/risers and shoot water out the exhaust. The diesel ship engines are beasts, can take a beating, and run for 10x as many hours as a gas engine. It looks like they are too heavy for aircraft but there are some Diesel engine manufacturers listed on Wikipedia.
- cardiffspaceman 4y ago
  Diesel engines on large ships typically work as diesel-electrics, the way railroad locomotives do. For example, Celebrity Solstice[1] uses diesel generators and azimuth thrust pods which contain electric motors. Celebrity Millennium[2] uses gas turbine generators and azimuth thrust pods. The electricity is also used for the rest of the electrical needs on the ship. The cruise industry is adopting LNG fuel, and hybrid power plants, gradually. [1] https://en.wikipedia.org/wiki/Celebrity_Solstice https://en.wikipedia.org/wiki/Celebrity_Solstice [2] https://en.wikipedia.org/wiki/Celebrity_Millennium https://en.wikipedia.org/wiki/Celebrity_Millennium

wolrah 4y ago

A truck engine is a great comparison point, because you can look at modern trucks for a perfect example of this. A Ford F-250 through F-450 pickup truck with the 6.7L "Power Stroke" diesel is rated for 475 HP and 1050 lb-ft of torque. The same engine in the same basic truck, but in commercial chassis-cab form, is rated for 330 HP and 825 lb-ft of torque. Step up to the medium duty F-650/750 chassis with a much larger cooling system and that engine is now rated for 270 HP and 700 lb-ft of torque, with optional software upgrades available for 300/725 or 330/750 configurations. The same applies to their gas motor, the pickup trucks get the 7.3L "Godzilla" engine with 430 HP and 475 lb-ft where the chassis-cabs and medium duty trucks get a 335 HP/468 lb-ft tune. The harder and more consistently the truck is expected to be worked the less power the engine is rated for. This isn't just a Ford thing either, GM and Ram also derate their commercial chassis compared to the pickups and the multiple power level thing on the medium duty diesels is common industry practice. Often the highest horsepower packages on larger diesels will be restricted to RV and/or emergency response applications where short bursts of power are more important than the ability to run hard for hours on end.

sokoloff 4y ago
As a point of reference to airplane engines, my first airplane made 230 HP @2700 RPM from 470 cubic inches (7.7 liters). My current airplane makes 325 HP @2700 RPM from 550 ci (9 liters).
- hnuser123456 4y ago
  How fast does it go?
  - sokoloff 4y ago
    First was a Skylane (fixed gear, fairly draggy) and would do 135-140 knots on 12-ish gallons per hour. Second is an A36TN (retractable gear, turbo-normalized) and will do 185-ish knots (215-ish mph) on 15-16 gph.