So is the stock 3/8 fuel water separator fine then as well?

It s highly likely a 3/8" fuel line system is adequate. If you are concerned, rig a temp fuel pressure gauge at or near the carb to confirm your FP at WOT.

I would throw your pickup tube in the trash. When you screw the 3/8 pipe fitting into the elbow on that tube it creates a very small are for the fuel to take its turn out of the top of the tank. I always use a 5/8 pickup tube. Thread the end of the 5/8 tube get a -10 ORB to -10 fitting tap the ORB side of the fitting to match the thread on the tube. I like fine thread cause you get more are of contact and its stronger. Then I drill the bung in the tank with a 3/4 drill bit and tap to 7/8-14 then screw the new tube in. I've done a bunch this way for myself and others and it seems to work pretty good. The hardest part is getting the die started on the stainless steel tube. Usually alot easier if you have a lathe handy...

While building my 496, I wanted to see the fuel supply from the tank. Here is what I found, good thing I looked. The plastic tube with the screen had fallen off, I had to fish it out the fuel sender hole.



We took a -8 90' 3/8" fitting, reamed it to fit 1/2" fuel tubing and pressed it in with locktite. So far has worked great for 2 seasons.



-Tom.

I don't run fuel water seperators either. Shouldn't be putting water in your gas tank anyhow. Fuel water seperators end up putting air bubbles in the fuel if you have a motor that demands alot of fuel they do not flow very well. There are some good one out there but they run around $600. I run an inline 10 micron filter. When you setup a fuel system 90 degree fittings are a big no no. They drastically cut down the flow of the system...

As mentioned, the fitting size isn't the problem. The problem is the small hole in that pickup where the tube meets the 90* square fitting on top. Once you screw the adapter fitting into it, you end up blocking off some or most of the hole. I have seen them where you are left with only about 1/8" hole once the fitting is screwed into it. We have just been making our own pickups. I use a 3/8"NPT x #10 SS fitting. I bore the 3/8" side out to the same ID as the #10 side. We use SS since the aluminum can become rather weak once bored out to #10. We then Tig weld a piece of 1/2" ID SS tubing to the fitting. We have been using them for over 10 years and they work great. Let me know if you would like one. I would be glad to build one for you. Here are some pics of our pickup along with a similar pickup to what you have now.
Eddie

Eddie,

How big of efi motors do you run on a pickup like that?

We have done 1000 hp with the same pickup. This exact one went in a boat with 945 hp.
Eddie