I am collecting the pieces, parts and approvals to convert my 1974 Warrior to the O-360 engine. The hardest part is getting the appropriate parts. I am down to the engine and have been researching the various ways to find a O-360 A4A or A4M--not an easy task. I am not excited about buying a prop strike engine from a salvage yard, though I am tempted. The prop strike inspection process makes me nervous, both about future safety and expense. Obviously, a storm damaged engine with no powered strike would be best but those come and go quickly.
Two expensive options are available. One, an unlike kind exchange for a Lycoming factory rebuilt O-360 A4M for about $32K. The engine would hold its value very well. That would be my wish if finances were not an option. Factory overhaul exchange is not an option as there is an age limit on my block. The unlike kind surcharge is $4K.
The second expensive option is a Penn Yann conversion of the O-320E3D to O-360A4M. This involves a reuse of the block and accessory case, which appear to be common to both the O-320 and O-360. The internal parts are changed however, basically a stroke modification. I have not been able to get an explanation from Penn Yann about the authority for conversion however. They say an STC is not involved but rather a "FAA approval". I can't find anything at the FAA either for an STC or some other type of such a modification. Penn Yann says there will be two data plates on the engine, one the original O-320 and the second for the conversion. My A&P says to be careful as the engine may not be viewed as a normal O-360.
Does anyone have any information or experience of this process of transforming a O-320 (E3D in this case) to a O-360?
Two expensive options are available. One, an unlike kind exchange for a Lycoming factory rebuilt O-360 A4M for about $32K. The engine would hold its value very well. That would be my wish if finances were not an option. Factory overhaul exchange is not an option as there is an age limit on my block. The unlike kind surcharge is $4K.
The second expensive option is a Penn Yann conversion of the O-320E3D to O-360A4M. This involves a reuse of the block and accessory case, which appear to be common to both the O-320 and O-360. The internal parts are changed however, basically a stroke modification. I have not been able to get an explanation from Penn Yann about the authority for conversion however. They say an STC is not involved but rather a "FAA approval". I can't find anything at the FAA either for an STC or some other type of such a modification. Penn Yann says there will be two data plates on the engine, one the original O-320 and the second for the conversion. My A&P says to be careful as the engine may not be viewed as a normal O-360.
Does anyone have any information or experience of this process of transforming a O-320 (E3D in this case) to a O-360?
