fuel line size to length ratio?
 

My main tank under my console back to my outboard will stretch my fuel length about 12 foot total. Should I change the size of my fuel line from 5/16 to a bigger I.D. hose?

5/16 is probably fine, but If you are going to replace it anyways, I'd go ahead and use 3/8

Yea its gonna be all brand new USCG approved fuel line. So 3/8 it is. Thanks for the help.

make sure you use A1 rated line, you can use B1 for above deck

This line gonna run below deck in my Chase tube.

I always used 3/8 on all mine, 150 to 225 hp, no issues.