Originally Posted by
2W0EPI
Funny you should say but I have come across manufactures exaggerations quite routinely whilst comparing data between engines.But it's all relative, so I doubt the 46 will reach 16000 rpm as stated in the manufactures manual?
Oh, it will reach that, because that is purely a function of which prop you fit... With an APC 10 x 6 or similar "ridiculous small" prop or so, it most likely will... And IF it does, it will punch out 1,6 hp, but with probably an unacceptable amount of noise, an awfully high fuel consumption, heaps of wear and tear and a prop that will not work very well on most common planes that could use that kind of output. I mean, a Wofgang Matt Saphir is a 180 cm wingspan aerobatic (I fly one, is how I know) would be perfectly powered with about 1,5 hp, but won't go anywhere behind a 10 x 6. That thing wants a 12 x 11 at 10K, works much better.
So the claims are not per se false, they are just outside the envelope of useful RPM and performance.
Whichever the case, 1,6 HP @ 12K, even the famous Hanno Special did not manage that, and that was a near 10% larger engine, WITH a tuned pipe...
(I know... the Hanno was tested by Peter Chinn at 1,8 HP @ 18K but that was without the pipe and on props FAR outside its recommended range. It was however sold with a factory-tuned pipe set up to do 1,5 hp @10K and things stopped there in real life applications. OS never released those numbers because they would hurt their claim of "strongest engine" while the base-engine for the Hanno Special, the RF, went to 2,1 hp)