I completely agree... The intake charge would have to be extremely dense to achieve those kinds of numbers in such a small space, if it is even possible, and I don't see any turbos.
Also, 4000 ft-lbs at 3000 RPM is kind of meaningless because torque numbers can easily be changed to whatever you want with gearing. Power figures would be much more appropriate, or at least give output shaft speeds along with the engine RPM.
Eh, I'm always extremely skeptical anytime I see such exorbitant claims.
Gonneville, those designs are sweet! I havn't seen most of those before...