I am not sure there is a power loss if this conversion is done correctly. Years ago when tractors were available with gasoline or propane the propane burners produced slightly MORE power. I am not positive that in every single case this occured, but as a rule propane had more power than gasoline. The thing is it must be done properly. On the tractors, the manufacturers always upped the compression, and I am sure the manufacturers got the timing figured out for maximum efficiency and power as well.
I will guarantee you that if you use a dual fuel carburetor there will be a power loss. The only way to do it right is to use a carburetor designed for LP.
I am convinced that if you convert an engine with low compression ratio to run on today's gasoline, along with running a dual fuel carburetor you are not going to be happy with the results either from a power or efficiency standpoint. In the past when I have converted an engine, I have not been happy with the results but it was always with a low compression engine.
