Could it be the Rossi mini tuned pipe holding it back ?
Could be....that is really the run-of -the-mill pipe for the Rossi's. They do
a fine job for what they are, but I would expect better performance with a
better pipe. I get over 18K out of my .45 with a Rossi long pipe....
....and it is a generic pipe for the 45 through 60. I would suspect it would
work fine on the 51 as well, but you would probably have to go down to a
9-7, 9-8 prop for some serious RPM.
You might want to try something other than the APC prop as well for RPM.
FBD.
