Fuel pipe size?
 

I'm about to run my fuel lines and just wondering what size I should use.

I've got some 10mm copper pipe that I had in the garage is it ok to use that and change the 8mm barb on the carb to a 10mm one or do I need to run 8mm copper pipe? Does anyone know the thread?

Also do I need to run a return or can I do it later if needs be. Currently running a pinto on standard carb.

If you have any intention of going injection fit two 10 mm pipes,fit two anyway and it will save you hassle later.
Better too much than too little.

I'll go for 10mm then, save me a couple of quid ect.