Guys, as a between semester project, my son and I had an engine custom built ...96 block .. vortec heads ... Comp Cam XR276 Roller ... All new internals ... GM vortec performance intake ...engine was balanced ... the works ... Him and I installed it, new clutch and flywheel ( because of 1 piece seal deal ... ) .. Had to intergrate electronic fuel pump and pressure switch into setup ...Hey, we had a great time bonding .... BUT , now that he is a day away from going back to school, we are having issues keeping the car running ..It seems to be loading up ...We had a backfire or 2, but now we have the timing straight. ...I believe the fuel pressure ( max 7 psi ) is overpowering the carb... When we do have it running, we have to keep the rpms really high, but it still eventually shuts down and has even sprayed a little gas out the top of the carb once or twice ... I have an old 650 DP,but I have had it since 1984, so I am reluctant to clean and try it...Maybe I'll go q-jet hunting, but I am soliciting advice and possible verification of the fuel pressure issue ... I did not think I would need a regulator with 7 psi. If I got one, would I need a return line... Anyone care to offer any other car recommendations ... Any answer tonight would be great. I want my son to take it for a spin before he leaves for college. Thanks in advance ... Steven Sr

Hi ,i think you have a needle/seat problem in your carb ,maybe your float has a pinhole etc.etc.
7psi is correct,most four barrels run fine until you hit 8 psi.
I think you should take the carb apart and check for small specks of dirt in the needle assy.

Good Luck

Well guys, I went back out on the driveway to curse at the car , and lo and behold, what do I see !!! We had not put the EGR block-off plate on ... So, we installed it and va-va-va-boom, the car will now idle ... We tinkered with the timing and idle mixture settings, try to get a good idle with vacuum and just a little of the lope present ... With my cheap Sears dialback light, I go to approximately 36* to zero the mark on the balancer ... I don't know how accurate my light is, so I'll plan to go by the builder to assist with the tuning..Wish me luck ... Thanks guys ... chow