Stirlingengineforum.com

Just thought I would share some recent (recent to me anyway) discoveries. I decided to make a new power piston connecting rod for my LTD engine to eleminate a small knock that was bugging me and also decided to shorten the stroke as well. What I discoved was the shorter stoke lowered the compression a fair amount and this in turn allows my engine to run at a much lower input temp. It will now run eight minutes after I blow out the candle, it used to be about three and a half. I also needed to lighten the flyweel as well to get the running speed back up. As for power outut, it's close to the same. I am still able to run a small home made alternator that powers two LED's. It's not quite at "palm of your hand" running, I never expected it to be but it's very close now, the candle is almost too much.

This experimental finding matches with LTD stirling engine analytical work as well as published experimental findings. Many experimental LTD engines have variable power piston stroke in order to re-adjust the swept volume of the power piston based on the running temperature difference.