Fuel system issues

That is the one I used on the 340 and use on my 416. What you may have is a restriction between the pump and the fuel pressure regulator. My fish still has the stock fuel line between the fuel pump/filter and the regulator but the car does not seem to run out of fuel on a good pull like the end of a track run. yeah, the AN6 line is sitting on the workbench ready to install to replace it. My fuel pressure gage is on the regulator under the hood so no real idea if the carb is getting starved at high power or not. It may be and that is why the larger fuel line will be going in. The dyno sheet shows about 40 GPH at 6000 RPM which I KNOW that little line will not support since I tested the flow in the shop and it is just under that.

<well instead of it starting at 5400 it is now at 5800 in second, nothing in first...>

That isn't making sense... do you mean started missing or something?