ORIGINAL: Pat Roy
Pe,
I understand what they do but the issue, if you want to call it that, is having a set of pipes that are inside the plane. If, and it's a real big if, I was ever to attend an IMAC meet as a competitor there would be a big hit on the scale appearence due to a pair of pipes running almost the full length of the plane under the fuselage. Now to build a plane from the ground up o accomodate the pipes would be another story but a large part of the internal structure would be lost to the pipes, and isolating the heat.
There has to be another way that maintains airframe cosmetics. These things are like hanging a pair of giant Peterbuilt intake cans on the side of a Mercedes.
Pat,
They sure know how to integrate the pipes in the looks of motorbikes. If they could make them smaller, they would, but the physics won't be fooled.
@ Bterry,
Altitude will not change rpm for a certain prop, because the lower load will be compensated by the lower available oxygen for the combustion, power will be even lower though like you already stated.
4.52 horses, and 30.5 lbs thrust is what I calculate from your data at your altitude.