New Gas Tank, New Problems

[kalel14]

My gas tank sprung a leak on my 1970 Convertible. The tank had the plastic valve on the driver's side for an EEC system, but the car did not have one. Since at one point that valve sprung a leak, I bought a new tank without EEC. I assumed the old tank was from a later model, since the car had some rear end damage at one point in her life and the parts were a mix of years (like no fiber optics in the tail lights).

Well the new tank doesn't have the EEC fitting, but it also does not have a fitting for the return line from the fuel pump.

Can I just block this line off, or is the pressure too high? Do I need to buy a fuel pump without the return line? What does this line do anyway? Does this mean I need a vented cap? How do I know if my current cap is vented?

 

[Crimson Thunder]

Is your 70 a LT-1. LT-1 cars did not have a return line but all the other cars did. I would advise running a stock fuel pump that has a return line.Running a "deadhead" type fuel system can lead to all kinds of vapor lock problems. Your car came with a sealed cap from the factory.