fuel line size ?

[cosworth.24v]

is there a standard fuel line size for a 3 litre ? if you look closely on this pic the blue (water) line between the air filter and manifold is how the fuel line is connected and needs changing but im unsure which mm line to replace it with any ideas ???????[attachmentid=2242]it did used to eat petrol ive put a tenner in before and driven 13 miles quickly and ran out before i could hit a garage (that seem a lot ????)

[sierra3dr]

I'm only going off my XR4i,it could be 8mm. 8mm I suspect is a general size