I have been told that the AN stands for Army Navy and were designed originally for military. Can anyone back that up, if this is the case why in the hell would the Coast Guard not approve it.
I used 6AN hoses and fittings on mine. I have very short runs, my longest hose is maybe 3' long. If I had to do it over I would have used 8AN for future upgrades.
Not sure if this makes a difference but I have a return line with Holley MPI at 42psi.

i have heard army navy and also aircraft something? either way they are being used in airplanes and they are super strict on stuff like that from my understandings....

I considered braided lines on my fuel system, knowing full-well they were better than rubber. Then the possibility of an insurance claim entered my mind and decided not to give the insurance company ANY leeway if the boat were to catch fire. I could hear the adjuster, " Sorry, claim is denied. Fuel line was not Coast Guard approved." That's just me.

I have spend hours researching this and I agree. It might not be right, but it must be C.G. approved.

If that is the case, skip the rubber and have hardline bent up. Looks awesome if polished and should hold up better than rubber.

I am not trying to bust your chops, but I see this all the time. This is folklore. Read your policy and look for the exclusion that says that if you use non coast guard approved equipment your claim can be denied. You will not find such an exclusion.

The biggest problem with using SS braided hose and why it is not CG approved on a fuel system is that it could easily come in contact with a +12 volt power source, cause a spark and catch on fire. Because the braided hose is in contact with the engine, carb, etc. it will be grounded. If it were to touch a power source like a battery cable, alternator lead, ignition coil, etc it would cause a hell of a spark. It could get hot, melt the inner rubber hose, leak fuel and cause a fire.
I use Push-loc hose. Generally I use -10. In this case with the potential of 625+ hp, I would go with -10, which has a 5/8" ID.
Eddie

Eddie,
Not trying to get this thread off path but what fuel cooler can we use with a -10 between the pump and motor on an EFI application, or should ot be left out?
Thanks
cbell

I don't use a cooler. As long as you return the fuel to the tank there is no need for a cooler. If you insist on using a cooler, don't put it in the pressure side of the fuel system. You want to put it in the return side, ie. after the regulator.
Eddie

can't see where the braided would be any different there as with solid steel that they like to use...