I just did the carb swap and my fuel pressure wont go below 7psi with the mallory bypass regulator.Is the 255lph pump in my tank to much?Should I use another regulator in line to drop the pressure more?Im using a edelbrock carb.

 

Might not be the regulator..your return line might not be sufficient.

Run a section of thick hose from the return fitting on the reg to a jerry can as close as possible. Run the pump. If the pressure will go below 7..you know it's the return line.


Don't run 2 regs inline.

 

You can also try to bleed any air out of the regulator as per Mallory's directions.I had the same problem with fuel pressure when I first redid my fuel system and when I bled it I was able to adjust it down to 2-3psi..but naturally set it at 6psi.To bleed it take out the adjusting nut and turn on the key or switch..whichever will activate the fuel pump..let it run for a couple seconds or so..you should see 0psi on the gauge..if not your return line is too small or there is a restriction as Jester posted above.If you see 0psi put the adjusting screw back in while the pump is running and set your fuel pressure.

 

The way Im running the regulator now is with the screw all the way out not even touching the spring.Out of the regulator bypass I have a 6an-3/8in fitting going to a 6an 45*hose end with 6an hose 6an strait on the other end connected to this fitting on the stock return line.I dont know if you can picture it how its run by the way I described it.Maybe the 45*is choking it?

 

I just checked the pressure again and its at 6psi so I guess there was just somthing stuck in the return.