Fuel Line Sizing
 

So, Josh@yoshifab hooked me up with a ridiculous NUKE performance fuel pressure regulator, and since I already have a 400 lph pump and 1000cc injectors and long term plans for a big turbo, it seems not unreasonable to put in some big fuel lines while I am at it. Especially since I have a flex fuel sensor and likely will run e85 at some point.

So, can you just use a huge pump, a regulator at the far end, and the OEM lines? Perhaps for the feed, but the return I imagine must be bigger.

Anyone have any definitive experience on what works and what doesn't? How concerned should I be that my flex fuel sensor has small diameter feeds (it's off a taurus or something)? What's a good fuel filter? I'm current using a corvette one since it flows a lot and has a regulator, but I want something manifold referenced. Can I just plug it's return line and keep it?

I have stable fuel pressure at idle with the stock lines and the wally 400e85 (465LPH). What flex fuel sensor are you using? Some of them list their flow limit the one's that I can think of, like the flyin miata one only can flow like 180lph (or something around there) so they'll funk up your idle fuel pressure since they go in the return line.

But maybe going up from -5 to -6 lines in both directions would be an improvement flow wise, but I'm not too worried about my 900cc injectors outflowing my lines and pump.

Huh, I would have put it in the feed, guess it depends how restrictive it is. I'll try to find out. Since it's a junkyard part, I doubt it's rated for a lot more than the original car.

As long as the return can handle the flow, everything's good. I guess I could always have the FlexFuel sensor on a t/bypass or something, with a slight restriction on the other side - as long as it gets SOME flow, it should be fine.

So, anyone recycle the carbon canister line on the NB's to make a return out of it?