New Fuel pump

[not_sure]

I found a pump that put out 4-7 #s of pressure compared to the one I had that only put out 3#s. The noise I heard that I thought could be a pulled head stud or exaust leak has now gotten alot less audible. I really never had the noise until I changed pumps to the lower pressure pump. Could this have been the motor chocking down from not enough fuel? I need to retweak the carbs now since I have better pressure to see If the noise goes away completly. Any ideas?