[Fot] gas blowing back thru carbs

[KENMUN at aol.com]

recently had a chance to try the rebuilt tr3 motor on the race track and  
experienced a strange problem. gas is blowing back thru the carbs. it's both  
carbs and the gas is on the inside fender well, underside of hood, top side 
of  the front fender, and leading edge of the rear fender .anyone have any  
idea what's going on? seems like the intake valves are leaking or the valve 
 timing is retarded. any ideas/tests or suggestions appreciated.
ken m. vintage tr3 racer