Ram Eco-Diesel vs F150 2.7 TT - Davis Dam
You just know it's not gonna be close! So which is better? Horsepower or torque lol. (The answer is both, apparently.)
Forum Discussion
RoyJ wrote:wilber1 wrote:RoyJ wrote:wilber1 wrote:
Want to muddy the water with turboprops? Better not.
Or even worse, ultra-high bypass ratio turbofans, where a significant amount of thrust comes from the intake fan turned by, gasp, torque...
True but RPM determines how much power is being produced by that torque and of course in the case of rocket engines, none of it is produced by torque.
Yes. What I meant is a turbofan produces both direct thrust (via jet nozzle) and propulsion via fan/prop.
On a 0 bypass turbojet, or rocket, it's all thrust. (shaft power negligible)
On a turboprop, it's all shaft power. (exhaust stream negligible)
Therefore a turbofan is the most difficult to calculate. Industry rates them by thrust for simplicity sake, but it produces significant shaft horsepower. Its ratio of shaft power vs thrust power changes with altitude.
Engine manufacturers don't even agree on which power setting parameter to use. GE uses fan speed, N1, for all its turbo fans. Pratt and Whitney and Rolls Royce use engine pressure ratio, EPR, but not necessarily in the same way, depnding on the engine.
