I just put a video on U-Tube of my test flight shutting down first rear engine and then the front engine under differant conditions. We had 3 men on board total weight 620 pounds.
With tanks near full, 138 gallons total 828 pounds. We had no trouble maintaining level flight and could even climb after feathering prop. This is with I/O 360 engines normally asperated and near gross weight. We were at 6,000 feet over our airport with temp. 55 degree F. We did this for a test, to prove for a mechanic, that was getting suided by someone. They said
a 337 would not fly on one engine. They had a supper charger fail that the mechanic worked on, therefore they had to shut down the rear engine. After passing 2 airports they tried to fly back to were they came from and crashed some miles short of that airport. Look at my video on U-Tube
http://youtu.be/tAB486BKI10