Quote Originally Posted by KaiserBill View Post
You're jeep is built to SAE standard inch pattern tolerances and guess what not every Jeep is exactly the same. So, your point shows me you've never worked with any manufacturing process otherwise you would know just as I do that advertised power or torque is often less than or greater than what you get out of an engine. Because of various factors found within the manufacturing process.
I think you're missing the point of all of this. I am well aware of manufacturing tolerances. The goal here is NOT to perfectly simulate one specific vehicle with its own specific combinations of variations within tolerances. That would be ridiculously complicated.

The goal is to get a general comparison of potential between the different power mods. Just like when comparing dyno charts, it must be taken with a grain of salt with the understanding that there are margins of error. I cannot possibly actually take into account all margins of error in my calculations to produce a "range" of possible results. The best I can do is acknowledge that there are margins of error. I have provided full disclosure on where I got my data, what assumptions were made, etc. It is up to you, the viewer, to take this all into consideration when viewing the results and realize that the results are not perfect, but are at least good enough to identify larger scale differences and trends.


Quote Originally Posted by KaiserBill View Post
I just think you need to realize that when you take into account all the possible areas for margin of error in the process you will find that 33% drivetrain loss is pretty high
Maybe we're just talking completely different languages. When I say "drivetrain loss", I am specifically referring to what is is commonly called "drivetrain loss" among automotive enthusiasts, which is a representation of the difference between manufacturer claimed crank hp numbers, and whp numbers as measured by a chassis dyno during an dynamic acceleration sweep through the rpm range.

By this definition, you cannot possibly tell me that 33% is not correct for the Wrangler, because that is exactly what multiple sources have found to be the difference between the manufacturer's claimed crank hp for the Pentastar in the Wrangler (285 bhp) and the measured whp on a dyno (~190 whp). 190 is 33% less than 285. This is not debatable.

You may be talking about steady-state drivetrain loss, which is the amount of drivetrain loss while maintaining a steady speed. As I described in an earlier post already, this completely removes the drivetrain lost due to moment of inertia because there is no acceleration occurring. This leads to dyno results that are much higher, and therefore drivetrain loss amounts/percentages that are much lower. However, this is not a realistic result for analyzing how quickly a vehicle might be able to accelerate, because in order to accelerate the vehicle, you must accelerate the drivetrain, which will cause additional drivetrain loss due to moment of inertia of drivetrain components resisting rotational acceleration. Steady-state drivetrain loss is most useful for analyzing a vehicle's steady state cruising efficiency.