ORIGINAL: OUTCAST
Dar, thats what I was trying to say in my post.
Thats why I spun one prop at 12,000 and the other at 12,800, so they would both consume the same horsepower.
I thought that would approximate the effect the prop change would make on the same engine.
Any yes I know there would be a variable because of porting, that was the comparison between the Rossi and the LA.
Now if we could only get the manufactures to publish the torque curve so we know where to start.
Of course...
It would be easier re-inventing the wheel than to ask engine manufacturers to advertize an actual torque curve, which they will need to guarantee...
Claiming huge HP numbers at RPM levels 99.9% of their users will never approach and of the remaining 0.1% 0ver 99% will never bother to calculate the actual HP output.... Yeah, that's much easier.
The HP (and thus the torque) curve can be plotted from testing an engine with various props. And then using the Reivers PropPower calculator you can put actual number on a graph.
Go to [link=http://mvvs.nl/prop-power-calculator.xls]this web site[/link].
You can either use it on-line, or download it and use MS Excel, or the equivalent 'Open Office' application to use it on your PC.