No joke: 248mph Hurricane dh5-20, 230mph Spit... what on earth is going on??

[trademe900]

Ok, Lolsav's post has brought me to some startling findings...I am positive I am seeing clearly but you guys should see this for yourselves. Forgive me if this has been posted but there is definitely not one post i've read this in.

I always thought the Spit 1 and dh5-20 were slower in outright speed than the constant speed propellers. At least on Repka the 2a seems to be slightly faster than the 1 in outright speed on the deck. Well it seems Lolsav is definitely right; that is in fact not the case up higher and there's also another surprise!

17,000 feet:

dh5-20: 248mph (course/low rpm)
rotol 100octane with tit pulled: 220mph (just before engine blows)

Spit 1: 265mph (course/low rpm)
Spit 1a 100oct with full emergency boost: 230mph (just before engine blows)
Spit 2a full emergency boost: 230mph

Please test for yourself folks, I am not seeing things here.