Trying to find out about this engine. Only marking is under exhaust port it says COX Made in USA. The engine in picture is Webra .40 to compare size. Looks like it was made for gasoline and points setup. Can see 2 rings threw the exhaust port. Has primer button on carb. Piston is 1.247" dia stroke is 1.158". Just trying to find out information on this engine. Didn't know Cox ever made anything this big. Would apprecite any information I can get.