4 weeks ago my 1973 all of a sudden died whilst driving. Had it once before, normal starting driving and after a few mls blop blop cough quiet. Except for the extremely loud noises coming form the trunk, like a cat was being killed. Starting, nothing. Waited for 10 min and no problems at all. 2 weeks ago same. Had my Bosch pump replaced for a new one, new Fuel Filter. Today, after having driven 80km's same happened again. Waited 10 min, started again, lumpy ride this time, lots of noises from the pump area. Managed to get home, had dinner, went out, started and running like a charm, no funny sounds or noise whatsoever, drove another 20 mls (not sparing the car) nothing, no problems, just a very smooth ride. Pump has a good gravity feed. Could it be the PRV or just crud in the tank blocking the outflow? Running unleaded fuel, no changes made due to that (to my knowledge), tank most likely the original one, not tampered with or relined. The sound (if it sounds and the car dies on me) is really from the pump/hoses/PRV area. Any clues anyone?