I want to thank Paul Lamar for his recent article on the Turbo Compound
R3350.  The R3350 was developed at a time when I had an intense interest in
airplanes, and I always wondered how an engine rated at 2200 hp (in the B29)
could be developed to 3500 hp.  I had heard of a 2700 hp version of the R3350
that was powering the Super Connies and DC-7s of that era, and I could
believe this given the improvement in av gas, exhaust valves, and two (or three)
stage superchargers, but 3350 hp seemed such a stretch.  Well, you made it
clear with your excellent explanation of the efficiencies and turbine
augmentation of the turbo compounding.  I suspect that all 3500 hp would have been
needed for the B-29 to have bombed Germany from North America.
I found it strange that this article would appear in a magazine on home
built aircraft, as having a spare R3350 in the garage seems unlikely.  Still,
it was such a good article that I am glad I found it.
dick crawford