I have exceeded the output of my fuel system. I have been searching old post and I know this has been figured out. Cannot find the information on how to modify the pick up tubes. Have 3/8" NPT female on the tank and need to maximize the fuel volume. Going to step up from -6 an to -8 an on the intake side of the fuel pump and upgrade the fuel pump.

Does the fitting on the tank come off?? When I went up on size I was able to simply replace the fitting.

Unfortunately no, 3/8" thread on tank. Worked fine for 500 HP, not for 600+.

then if you cant do that, you are going to have to have a new pickup tube made and installed.

Correction, I will have to make a new pickup tube and install it. LOL Pre-made off the shelf tubes that I have seen will not do what I need.

dont think you'll have an issue running -8 on a 3/8 pickup, hell Im running -10 on the whipples on stock pickups and way more that 600 ponies

Interesting, so maybe the pickup is not as big of a problem.

At That level, it depends on other things in the system too. :wink

It seems to be more complicated above 500HP.

Well if you dont want to weld on the tank, make a new pickup tube with a flange at the top that mounts like a the fuel level sender, then cut a hole and screw it down with a gasket.