Surge tank & high pressure fuel pump

A carburetor has a bowl of fuel to draw from in the event that the fuel pump sucks some air if the fuel in the tank is low  and sloshing around.  In a fuel injected car, there is no reserve and the fuel must be supplied at a specific pressure, so any air in the line from sloshing is bad. Fuel injected cars have baffles to trap the fuel around the pickup in the tank, but they are not present in a car designed for a carburetor.  There was a turbo brat with fuel injection for 2 years (I think) that had a baffled tank and would bolt in, but they are much more rare than a regular brat, especially 38 years later, so impractical to find.  So I'm installing a surge tank, which is essentially a small bowl of fuel that feeds the high pressure pump, keeping a steady supply.  Race cars typically use aluminum or stainless and that all seemed out of place in a cheap old car.  I settled on the following solution.  A marine fuel filter / water separator that has the necessary 4 ports already was a great place to start. 

 

The existing low pressure fuel pump supplies gas into the filter.  The high pressure pump draws from the filter.  The return from the fuel rail returns to the filter.  When the filter is completely full then the fuel returns to the tank.  I had to modify the fuel filter bracket just a little.  The two "in" ports are independent of each other, but the "out" ports are connected by the casting.  I tapped the casting on the overflow "out" and put a set screw in it to separate it from the high pressure pump feed "out".  I then had to drill into the casting after my plug to open up the overflow "out" so it would allow a full filter to return to the tank.  To mount it all, I decided on the drivers fender where the old jack holder was.  

I bent a bracket from 16 ga steel to support the filter, and then made a fuel pump bracket from 20 ga and used the toggle clamp from the stock fuel filter to close it. There is a rubber strip around the filter to dampen vibration and also hold it snug in the metal clamp.

 I've got both brackets screwed in for fit up, once I'm "finished" I'll go back and tack them in place.  I've got all the the lines mocked up with whatever hose I had lying around, I'll replace them with appropriate new fuel line and then I'll have the fuel system sorted! 

Some of the EJ swap write ups claim the stock return line is too small, but I'll give it a try and if it not able to keep up with the return feed I'll run a larger return line.  The stock brat return line is 1/4" and the supply is 5/16" by my measure.  I don't want to drop the tank and install a bigger bulkhead fitting for return, but I will if its necessary.