Wondering about the O-320B 160 hp narrow deck uses 3/8" prop bolts and .27 thick flange. There are mods available (Powerflow, porting, 9.5:1 pistons etc) to push it to 180 hp.
Lycoming went to 180 hp with the 360 they switched to 7/16 or 1/2" prop bolts and .38 thick flange.
Interesting that the mods can generate hp with a crank to prop setup that apparently didn't work out for Lycoming. Seems like Lycoming would have kept the same crank and flange if they could unless something failed during testing.
Especially with a long prop installed. Would the same be a concern with the 7/16 vs 1/2" bolts on pumped up O-360's over 200 hp experimental?
Lycoming went to 180 hp with the 360 they switched to 7/16 or 1/2" prop bolts and .38 thick flange.
Interesting that the mods can generate hp with a crank to prop setup that apparently didn't work out for Lycoming. Seems like Lycoming would have kept the same crank and flange if they could unless something failed during testing.
Especially with a long prop installed. Would the same be a concern with the 7/16 vs 1/2" bolts on pumped up O-360's over 200 hp experimental?