Adrenolin

Could someone explain to me ... 3/8in, 3/8in NPT and -6AN??

My carb intake is 3/8", my pump is 3/8 in. NPT, canister filter is 3/8" and my carb feed line says Inlet is -6 AN and Outlet 5/8-20 in. Not sure about the fitting for at the fuel tank.

I'm now attempting to figure out all the fittings & their sizes I need along with a fuel pressure gauge and its fitting.

Thanks.

fakesnakes

AN fittings are the # over 16, so 6AN is 6/16 or 3/8. They use a 37 degree sealing surface and are only compatible with other 6AN fittings. Do not use any tape or sealing compound as the seal is at the 37 degree flair.

NPT is pipe thread taper and seals at the thread, so tape or sealant is required on the threads. Adapters to convert AN to NPT are common and are what you see all over my GT40 fuel picture posted in another thread.

If you have a stock Mustang tank and pick up, it is either 5/16" or 3/8" nipple as is the fuel hard line. I recommend you get a 3/8" pick up and hard line as it will make your life much easier. You then have a choice in how you connect your fuel line. I think you said you have an electric pump. The easiest and cheapest way is to use 3/8 NPT to 3/8 hose fittings and connect the pick up to filter, filter to pump, pump to hard line with rubber fuel line. You can then use the stock hose nipple on the carb with a short piece of rubber fuel hose.

From there, the sky is the limit and only your imagination and wallet will limit you! You could run a complete AN set up and spend several hundred dollars. Tell me what you want to do and I'll send you a sample part list.

kalli

LOL even you are confused. guess how I feel about NPT/AN/ thread sizes.
i figured that 6AN is 6/16->3/8. the summit racing catalogue once mentioned it as a tech tip. but still I won't get a 6AN hose over a 3/8 nipple (you will eventually, but a lot of work ... or was it the other way round?)
and for some weird reason you can get 100 ft of 3/8 hose or a few dollar, but you can't get 6AN for less than 10 times that money.

Anyway I was wrecking my head over this once before as I bought a piping that had 6AN inlet for my carb and wanted to hook this up.

This time round I just went with 3/8 NPT nipples all the way through :-0

You can't imagine the amount of cursewords I have given NPT and AN so far :-]

Kalli

Adrenolin

Hey Mark.. thanks for that explanation & the tips as it helped a lot. I bought 20' stainless braided 6AN hose, a number of 6AN hose ends (straight & 90*), 6AN to 3/8 NPT adapters, a 6AN fuel pressure fitting with a 1/8" NPT port and a 0-16 liquid filled fuel pressure gauge.

I did use thread sealent on the male 3/8 NPT adapters running in/out of the pump and filter but none on the AN 37* ends.

Might still need a 180* fitting off the carb fuel rail as it runs forward into an inline filter.. this is where I'm thinking of the 180* back to the firewall, into the gauge, back through the tunnel or inside edge of passengers frame rail to the pump, filter, tank.

Total was under 250.00 and looks like I'll have a few feet and fittings left over.



Kalli.. the biggest thing for me was figuring out the different types of ends, fittings, adapters, etc. I still don't understand why there isn't a male 3/8 NPT hose end availabe! It would make more sense then using the 6AN hose end & a 6AN to 3/8 NPT adapter.. but they don't.. or at least not in the Summit brand. Ohh and trust me.. I can imagine and do understand the cursing over this. With Mark's explanation above and now having used it I understand it much better.

fakesnakes

Glad to hear you have it figured out. Do you have a dual inlet fuel rail? If so, simply flip it around, no need for a 180 degree fitting. The more turns you have, the harder the fuel pump works and the bigger risk of fuel starvation.