- Feb 12, 2006
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- Disclosures
- Development Engineer-Mesa Boogie, Development Engineer-Genzler (pedals), Product Support-Genz Benz
I think it depends entirely on the application. Those certifications are for a very specific industry (passenger automobile) and look at the engine HP only, they do not consider the rest of the drivertrain, nor do they represent usable HP at the wheels over the entire power band, just a single peak point. How wide this point is, and the slope on either side factor greatly into the real world performance.
Now like using a HI FI rating system for pro audio or MI power amps, using the certified HP rating doesn't work well for application specific prime movers like generators, where transient response, overload recovery, RPM overshoot. It also doesn't work well for engines used in locomotives, pumps, conveyors, line shaft applications, etc. ie. anything with a dynamic load component to it.
My (electrical) engineering field of study was in industrial control systems and I am keenly aware of how misleading a single, tidy, marketing driven number can be. A single number can work in a single speed static system, but nothing we have been discussing can be even remotely defined as a static system. The key rule to follow is to use static methods with static systems and dynamic methods with dynamic systems. Using a static design method or description to define a dynamic process is just wrong, though the marketing types seem to think it's ok because some of you guys buy into it.
Here's some interesting reading on another complicated (though interesting) subject: Horsepower - Wikipedia, the free encyclopedia
