You can get way more than 350 HP from a stock pump! I have 500+ HP 446 with a 6 pack and a hemi return filter and have plenty of fuel even with the fuel returning to the tank.

I also have 340 with eddie heads and hi compression 11-1 and have run the car three different years out at Bonneville at wide open throttle for more than 5 miles at a time with a hemi return filter and did not run out of fuel with a stock airtex mechanical fuel pump. I beat the car for many passes out there and never ran out of fuel even with a return line. How many can say they tested there fuel system that way?

Plus I have run many drag cars all the way to 3000 HP and know fuel systems well.

Your 360 is fine with a mechanical fuel pump and you don't need more from my experience unless you got money to burn and want to worry about vapor lock with the wrong sized pump and lines.

Like said above, plenty of fast cars with 5/16" lines and mechanical pumps.

That's what I was wondering. I feel like fuel systems end up way overbuilt a lot of times. Was really wanting some real world ets on stock stuff. I have a carter on the shelf I may stick on but I think I'll stick a gauge on it for curiosity sake first. Thanks fellas!