About to drop the 5.3 in my v6 truck. Engine is a 5.3 with heads, cam and nitrous. I have 8.1 marine injectors and an in tank Walbro in stock bucket. The stock v6 hard lines are still there but the soft line going to the tank/fuel pump has all been cut. Trying to figure out what size line and connectors I need to get.

 

3/8" and 5/16"

 

fra-491990

fra-491992

Honestly if its a budget build, go to Oreilly's/NAPA/AZ and get the plastic ones in the above sizes with barbs then just use a fuel line clamp.

 

It's not a budget build. It's a show truck I just decided to swap

 

3/8 is 6an right? The nitrous kit I got from nx is all 4an. Will that work or no

 

That's correct. 1/16" is 1 -an. If it's a show truck, I would cut the flex off both ends of the OEM V6 tubing, use tubing compression to -an fittings to connect either a ss braided hose or startlite/similar then to those fittings I listed above.

I'm not sure I understand your question about the NX system. Most people just adapt the fuel supply line to the test port on their oem rail. That's what I did moons ago at least.