Joined
·
7,380 Posts
Another late update.
Problem FINALLY solved!
First I tried a mallory 140 gph elecrtric fuelpump but it only lived one hour new out of box before it failed and mallory was very hard to deal with worst customer support I have ever had deal with!
So decided to try a mech fuel pump again and went with a Holley 454-20 http://www.holley.com/12-454-20.asp this time instead of the old carter 172 gph. Very pleased with this Holley pump so far, still using the insulater between block and pump and most of the other things I tried earlier but removed the foam on the hose between the pump and carburetor. Instead of a regulator I decided to use a vapor return at the end of my carb fuel line tapped it for 1/8" npt and drilled a .050 hole in a brass npt plug and runs a return line to the tank. It gives me 6-7 psi at idle and 8 psi on highway no matter how hot it is or how long I have the car idle. Also replaced my homebuilt fuel sending unit with a RobbMc unit and the pressure is much more stable under acceleration not sure if it is the pump or sending unit? Im very pleased that I finally after 5 years has solved this problem.
Marcus
Problem FINALLY solved!
First I tried a mallory 140 gph elecrtric fuelpump but it only lived one hour new out of box before it failed and mallory was very hard to deal with worst customer support I have ever had deal with!
So decided to try a mech fuel pump again and went with a Holley 454-20 http://www.holley.com/12-454-20.asp this time instead of the old carter 172 gph. Very pleased with this Holley pump so far, still using the insulater between block and pump and most of the other things I tried earlier but removed the foam on the hose between the pump and carburetor. Instead of a regulator I decided to use a vapor return at the end of my carb fuel line tapped it for 1/8" npt and drilled a .050 hole in a brass npt plug and runs a return line to the tank. It gives me 6-7 psi at idle and 8 psi on highway no matter how hot it is or how long I have the car idle. Also replaced my homebuilt fuel sending unit with a RobbMc unit and the pressure is much more stable under acceleration not sure if it is the pump or sending unit? Im very pleased that I finally after 5 years has solved this problem.
Marcus
