I was doing the "Feed The Beast mod" tonight... and thought after I took out the fitting with the screen in it, that is on the injection pump, why not make the inlet EVEN BIGGER?

Anyways, had some T304 stainless tubing laying around, and it looked like a pretty good size (3/8" I.D. to be exact). Figured out how to completely disassemble the thing and ended up arc welding it together with 308L-17 (stainless rod). Did my own "heat treat" process on it, cleaned like it was going out of style, and reassembled. This was the end result.
Thought I'd share my "little" accomplishment.

What you you guys think,
too big?
too small?
never too big?

In the pictures, from left to right, my Monster Inlet (3/8" I.D.), then the fitting used to upgrade the filter housing (1/4" I.D.), then the stock injection pump inlet (3/16" I.D.)

What did you reset the pressure to? You did take the pressure adjuster screw out?

Yes, fortunately I read a post about that earlier today. I noted the setting and set it back to where it was. I believe it was 8 1/2 turns in from initial thread engagement.

Yes overdid the fitting, as it can't flow any more than the id of plumbing from tank can flow (that is what I used to size the original FTB to), also unless you have bigger lift there are some dimensional restrictions internal to the GM pump, and have a look at the 4 holes under the screen you can't flow any more out of them than the cumulative total of those 4 holes, plus the pressure regulator needs to be set to get about 140 psi transfer pressure IIRC what DP & I set mine to on IP test stand, or maybe 125 I'm not sure.

Thank you for the input, if I remember correctly I read that the four holes flow enough to supply up to a 1/2" line, of course this is pointless because I knew the lift pump could only flow so much, and I am not up sizing the the sending unit in the tank, lift pump, all fuel lines, and all fittings. Heck I don't even have a running engine to put this on yet, hahaha.

If you all want to know what really provoked this fabrication...I went to Princess Auto (30 min. drive one way), and thought I got all the right fittings. Turns out I was wrong, got the wrong fittings, so began thinking of a cheap way to upgrade the size of the inlet with materials I had at the shop. When I finished (two hours later), I end up with this huge inlet fitting.

Takes a #4 ORB thread to NPT adapter & NPT barb fitting, or a #4 JIC fitting with barb/flare fitting, cut off the flare end and drill center to .280", the dia of 4 holes mite be same cumulative as 1/2" but I don't think so, I have one in glove box I'll measure tomorrow and do math, but I opened mine up,

FYI a FTB IP inlet fitting was on Heath's Bonneville racer, I sent him one to test next time he dynoed an engine just to see what the data shows on dyno, he never got to that but he did put it on the Bonneville Racer, so part of me was on the team there, and he had his own "special" lift pump.

and he had his own "special" lift pump.

Can you elaborate on this LP or is it "Top Secret"?

I don't know details other than it's big much bigger than any of us will ever need here, Walbro- FRB5 is plenty for performance, remember he was twin turbo and needing fuel to support 153 mph.

Maybe "Dual" like you?

Nope I'm Heath h/o (similar to factory) & Walbro in parallel, with selectable power to run one or other, normally I run the Walbro with Heath h/o in reserve. Bill would not share any more than it was a high volume pump, at one time I think they were considering FASS but passed on it for $$$ involved

10-4....I guess one needs to play some hands close to the vest....after all, he's doing things most 6.5ers are not.