Two problems need help
 

okay guys got some troubles with my z its a 1981 2 seater. 1st problem cant get the car to run for more than 30 min at a time. Car shuts off and doesnt want to turn on till it appears to cool down. Ive replaced the fuel filter, spark plugs and wires, o2 sensor on the exhaust. Was maybe thinking might be something with the distributor. 2nd problem it appears when i hit the gas I hear a like a thumping sound from the front of the vehicle by the resevoir on the right hand side. Dont know what it is. Any help please guys thanks.

a few things it could be but im leaning torwards the head temp sensor.. thats located below the #6 spark plug.. replace that and see if that helps it.. also your igniton modual might be going bad as well.. but normally when that goes back you can still start your car but itll keep dyin on you... hope that helps man..