Fuel line sizing for big singles
 

I know several of you have been running big singles in 28's with great success and I am in the process of replacing old fuel line and want it big enough so that I will not need to change it in the future. Will a 1/2" be good or stick with 3/8", as you know the run is short from the tank in these boats. Thanks, Chris

I'll take a look at what I did. I remember boring out the fitting to match on the tank and then running the matching size braided line from there. (-8 maybe)

I run 1/2" on my outboards individually. The big thing is the pick up in the tank and the fitting at the top. Most fuel systems this is the most over looked item. Make it as big as the bung in the tank will let you. I made the tanks for our tanks and used a larger bung for a larger pick up tube.

All depends on how much HP you want to support.

Minimum I would go if you plan on 500 HP or so would be 1/2 inch.
-10AN has an ID of just around 5/8" and I would go that way if you plan on more than 500 horses.

Change your tank fitting to a full flow radius type so it maintains the same ID as the line as well.

Agree with the post above -8 for say 500-600, -10 for anything above. Dont forget to upgrade your pickup as mentioned but also your water seperator, filter, etc All needs to be sized properly to work together.

I would also run a full return back to the tank if its not already there since you are in there making changes anyway.

I was told the same. 1/2" was good up to about 600hp and 5/8" for 600+. And good point on the pickups, filters, separators, etc.

I have the 110gph filter head and filter on the way, it is set up with 1/2" ports. Looked at the tank today and I have 2 good 3/8" feeds. I will plan on feeding 2 lines from the tank to 2 input ports on the filter then possibly feed -10 from one port to the pump and on to the carb. I don't plan on superchargers or turbos so a single carb would be all I need to feed. Thanks for the help