RE: Where do Stats come from?
The numbers to trust are the numbers guys like Dub Jett publish. OR the RCU tach forum is a other good place to find real world rpm figures.
Anything numbers the manufacturer puts out is bogus 99% of the time. Also, the rpm range the mfg puts on the engine means little as well. A tuned muffler can push an engine over the 'max' rpm easily. Doesn't hurt the engine unless you're trying to hit 20k on a 16k engine. I degree all of my engines to get a sense of where the powerband should be and prop them accordingly.