Fuel pump questions for 235

[wolffcub]

I installed a rear mount frame tank and a basic inline fuel pump from Napa. The issue im having is with the pump mounted half way between the tank and carbs it chatters like crazy causing a vibration all the time when its installed. When I disconnect it and let it hang in a downward bow with the line it goes nice a quiet and pumps quietly. I have tried to tilt it and lay it flat but when I always go to bolt it back up level it seems to cause that loud chatter. I can move it closer to the tank I guess but will that help the issue with what sounds like fuel starving? The line from the tank has to run in the upward direction for about 6 inches to get up to the frame rail to stay clear of the rear axle. Can this be my issue that the pump is not 100% gravity fed?

Should I just go back to a mechanical pump or get a better pump like the Holley Red? If I go back to mechanical what new style one do you recommend for the 235 im running?