Folks, there is issue about jap's aircraft engines that I found interesting.
Eg. Hayate was capable of some 630 kn/h, but the engine is said to have 1900 HP. Ki-100 had engine of 1500 HP, but it was capable of 590km/h only. Both planes seem to be aerodynamically clean, with moderate dimensions.
When I've asked this on another forum, people told me that engine makers, to put it simple, lied about power of their products. Is that true?