Help fuel pump question?

Been There. Done That.

You have the right idea about how to handle your quandry. Simply hook up the in and out lines on your Carter (in fact that's the same pump I chose) and then block off the return line from the tank. Apparently, the third line had a few intended purposes. First, it was meant to keep the fuel and the pump cooler in the long run, by looping it between the pump and the tank. Second, it was intended to pressurize the tank to keep it in compliance with EPA rules. There was a third rationale for use that was to effectively act as a pressure relief / stabilizer for the system. That's what I read in the manual, at least.

All that said, I've been running my Carter pump in the manner described for 5 years now, with no adverse effects noticed. Go for it!

pumps don't always put out what they are rated for. 6psi is the absolute max for an edelbrock. They recommend 5.5 and I recommend 5 for good measure. I say you should set up a regulator and a fuel pressure gauge. I had hard starting and fuel smell when warm when I was running too much pressure with my edelbrock, but no stumbling or anything. You can check your spark plugs to see if they are really black. If they are then you are consuming too much fuel, likely from the fuel pressure, and then your spark plugs are probably fouled.