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How come a 11L Diesel engine only made 300HP? Was the engine that ineficient at the time, compared to a modern engine?
by dragosmocrii 7y ago
How come a 11L Diesel engine only made 300HP? Was the engine that ineficient at the time, compared to a modern engine?
- rpeden 7y agoDiesels like this trend to produce relatively low horsepower, but lots of torque. As a comparison, here's a modern 11L diesel: https://www.macktrucks.com/powertrain-and-suspensions/engines/mp7/ https://www.macktrucks.com/powertrain-and-suspensions/engine... You'll notice that HP is 325-425, so not that dramatically different from the Snow Cruiser.
- SigmundA 7y agoMore than double the horsepower mainly due to turbo charging. That level of power is for commercial use, an 11L diesel can easily put out more than 1000hp based on the amount of boost but the longevity of the engine suffers and the power is not need for the application. Here is a Volvo 13L (The Mack MP7 is basically a Volvo D11) putting out 2500hp: https://www.motor1.com/news/94292/2400-hp-volvo-truck-seeks-world-speed-records/ https://www.motor1.com/news/94292/2400-hp-volvo-truck-seeks-...
- fffrantz 7y agoHorsepower are only one of the measurements for an engine. These engines have enormous amount of torque which is more important than sheer horsepower.
- gameswithgo 7y agoYou can multiply torque with gears, can't multiply horsepower. An engine with lots of torque is important because you can make a lot of horsepower at low rpm, important when you need to make a lot of horsepower for a long time, efficiently.
- LeonM 7y agoHorsepower (which has many definitions) is the torque output multiplied by the engine RPM (divided by some number to make it equal to the strength of an average horse). Since these engines operate in a relatively low RPM range, the HP number is not that high. Most countries switched to using kilowatts as a measure of vehicle engine power. Also remember that these are diesel engines from the late 1930's. This was before the development of 2-stroke (blown) or even turbocharged diesel engines. These engines were a lot less powerful compared to modern diesel engines.
- matt-attack 7y agoThe kilowatt measures precisely the same thing as horsepower. 1HP is approx 3/4 kW.
- LeifCarrotson 7y agoKilowatts are also a multiplication of RPM and torque - one horsepower is 0.7457 kW, no RPM factor required. High-redline gas engines compared to diesels will have more kilowatts than torque regardless of which system of measurement you use. You need low-speed torque with low fuel consumption to work at relatively high power output efficiently for long durations.
- LeonM 7y agoThat is correct. kW is used the same way as HP, except that kW is better standardized. There are many definitions of how much power a horse has, and just one definition of the watt. For example: the 'mechanical' HP (commonly used in the US) is the equivalent of 0.7457kW, but the 'metric' HP (commonly used in Europe) is 0.7345kW [0]. [0] https://en.wikipedia.org/wiki/Horsepower#Definitions https://en.wikipedia.org/wiki/Horsepower#Definitions
- SigmundA 7y agoThey are both units of power the fact that they have different numbers does not have bearing on the question asked, power is power, torque is torque regardless of units.
- YSFEJ4SWJUVU6 7y agoThe engine actually only made 150hp, but luckily there were 2 of them. Yes, they were certainly less efficient than modern engines. However, ICE engines have always had trade-offs between power output per size, mechanical efficiency and reliability, and for this vehicle the last one was certainly of most importance.
- SigmundA 7y agoThey lacked turbo charging which is necessary for diesel to make modern levels of power due to the low max rpm of the engines. Naturally aspirated diesel where relatively efficient they simply lack power.