Changa2

After about 7 months of building my own 383 (the fun part) and then installing it into an 87 Camaro I finally got it running today.

One thing I noticed was a large fluctuation on my fuel pressure gage, reading a rapid 3 to 9 PSI.

The 87 has an in-tank fuel pump and a mechanical pump (with return line), which I am using.

Why so much fluctuation?

BTW, I should add that I have pulled all of wires from from the pass. side harness route and have not rewired the fuel pump relay. I am not running a fuel pressure regulator either.

I started out with the stock pump (Carter with ret. port) just for simplicity, just to get it running. I have a nice new Edelbrock sitting on the bench. Would I be better off using that pump and just plug off the return line?

Thanks

Apeiron

The pressure from mechanical pumps tends to pulse each time the fuel pump lobe on the cam turns.