Thoughts, please. I was returning from an hour cross country in my J3C-65 hp Cub. I was focused on making a 3-point grass landing in a relative short distance. As soon the aircraft stopped the engine quit. The temperature was 90+ and the heat index 99, there were 4 gallons of fuel left in the tank. I pulled the stick all the way back quickly and forcefully applied the brakes. The engine would not restart. I was wondering if I might have gotten a vapor lock from my actions causing the engine to quit. Am concerned this might happen again away from my home airport. Thanks, Joe