Fuel Fitting Measurement, Source?

[Clair]

So, I'm trying to put together the last of the goodies I'll need to plumb my fuel lines, running aluminum hard line with tube nuts/sleeves for a few AN fittings here and there. I'm getting hung up on how to measure some NF/o-ring-type fittings. Specifically, on my fuel pump (electric, high pressure) the inlet and outlet each have different fittings... one for a hose barb, and one for an inverted flare fitting. I'd like to have a short piece of flex line on each end of the pump, so I'm trying to find an AN adapter to replace these two.

Question is: when measuring the size of a fitting, do you measure the OD of the threads, or the OD of the root of the threaded part?

FWIW:

<-------->
<|-root-|>
<-------->

|-threads-|
<-------->
<-------->
<-------->

I've attached a pic of both to illustrate without showing my ignorance too much more... In the pic, the fitting on the left is the inlet fitting, and has a 3/8" hose barb end and what I assume to be the 9/16-18 end that threads in to the pump. The pressure fitting, on the right, has some sort of tiny end (7/16-24 NF) which threads in to the pump, and has a 9/16-18 female end that works with 3/8" inverted flare fittings. What I'm trying to avoid is a string of 3 adapters in a row to get some flex line on to both ends of the pump. I guess I only need one end of flex line if push comes to shove, so that it'll be easier to service the pump if need be.

And do any of you know of the part I should be looking for that has the proper fitting for the pressure side: (7/16-24 NF) threads with an o-ring to seal, and a -6 fitting on the other end?


Thanks!
Clair

[chitown hustler]

Earls line of fittings sells the adapters your looking for pn# 985064erl = -6 male an to 7/16-20 o ring adapter "note not 7/16-24??? " pn# 985006erl = -6 male an to 9/16-18 o ring adapter Measure the o d of the threads or get a known size bolt from the hardware store to be sure . I,m curious what kind of fuel pump you have ? That outlet size is alfully small . As is the other size . Most are usually the same size and take pipe thread adapters.

[Clair]

Chitown,
I'm not real keen on the outlet size of this pump/fitting, either. It's basically a replacement pump for a Phord truck with EFI... it's one of the relatively generic pumps you can get that will feed a decently healthy V8 and still be on the cheap side. I'm setting up an EFI system on my Valiant, and that's why I need the high pressure stuff. I'm toying with the idea of drilling out the hole in the fitting, if the adapter is the same size or smaller... this fitting only has a 0.200" hole... but the pressure is 50+ psi before the regulator, so maybe it doesn't matter.
As for the Earl's parts, I'm looking at those. They're really the ony ones that seem to have the right o-ring adapters, and the price isn't bad.

Thanks for the input! Anyone else?

Clair