The fuel line limit is the legal capacity.The pressure line is open for you to test .From what I understand the guys to say is that a shorter or longer line effects teh response and smoothness of engine power as weel as being able to run a slightly leaner midrange with the longer line.
I would think taht a longer line could also help in a bit more fuel milage as it smooths out the power band.
Might be wrong ,would be great to get some experienced guys to comment too.
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