I kind of like the idea of running the fuel lines outside of the tunnel and outside of the car. Might be easier to see the leaks and better access if I need to get to it in the future. Are there any cons to this idea, beside the lines may be in harms way and exposed to the element?. Andy

My concern is that easier dammaged and resulting fire hazard.
I assume, dammage is not as likely if their tucked up in the cabin or in the tunnel. I'm no expert!
You might want to look at the PCA rules to see if there is anything mentioned. Or send a tech question to PCA Tech chair!

Most people run them inside and my personal pref is inside. It sounds bad but think about it the lines are already inside car car. Use gromits where you pass through sheetmetal or better yet use bulkhead fittings. For more safety get an impact cutoff switch. It kills the power to the fuel pump if you wreck the car. Summit and Performance products has them.

what size in inches (approx) is AN -10 hose diameter?

Dave,

I had the same questions re: the difference between AN12 and AN16. It was hard to find the ID of these fittings on the net, never did find a helpful site that laid it all out. FYI: AN16 are about .88" ID. AN12 is too small for engine to cooler lines.