For my MPFI setup on my 69 502 RS/SS 6-spd, I need to run two 10-AN lines (feed and return). Because the underbody of the unibody dips down once it gets past the front frame rails, the lines will be the lowest part of the car, and that makes me nervous (as in ripping them apart on a speed bump or something!).

Besides running them through the interior (insane!) or through the trans tunnel (likely not NHRA legal), I don't think there's another option.

I had first planned on using electrical conduit piping, but that's only a little more protection. So, my next though was to get some U-shaped iron and run a channel under there for the lines to pass through. Unfortunately, the underbody is by no means straight, so it would be tough to do.

Another thought I had was that if I install sub-frame connectors later, maybe they sit lower and I could run the lines beside one of them?

Any advice is well appreciated... I'm trying to do everything better, stronger, and safer than the factory would have, and this is definately not an area I want to compromise on... don't want to get roasted to death!

Thanks,
Dave

Run the lines from the tank to immediately to the outside the rail forward and over axle and up to the front spring hangar. This is the only place they will be lower.

Then, run them forward along the under the unibody about the verticle wall of the rocker panel to the front frame. Follow the frame up to the engine mount area on top of the rail.

Just do it in hardline.

Right Stuff would happily bend them up for you out of 7/16" or 1/2", steel or stainless, they'll even put the spring thing protectors on them.

I've also seen them run thru the rocker panels to get them up out of the way.

I would recommend the steel lines over the stainless flex lines. JImM has the right ticket. Safe and not that expensive.

Not sure how I would make a template that long for someone else to bend them... if I want to do it myself, a few questions:

How do I know what size will mate up to -8 or -10 connectors? I assume I can buy the pipe and nuts and stuff from Summit if I know what I need to get.

What kind of flaring tool do I need? Are AN fitting 47 degree?

AN is 37 degree
SAE is 45 degree

I "think" someone will correct if required...

-10 is 1/2"
-8 is 7/16"
-6 is 3/8"

Right stuff can easily bend up the full fuel line from the original pattern, get 2.
Then all you need to do is rebend and flare the front and the back end.

The stainless is pretty, very pretty, but it is VERY hard to bend, even in the standard 3/8" size. I'll never do it again with stainless, and I'm not happy with how mine turned out, but will live with them.

They make AN fittings that will couple to an SAE 45 degree hardline fitting.

Standard AN stuff is 37 degrees.

AN diameters are in 1/16 inches,
10 = 5/8 in
12 = 3/4 in
6 = 3/8 in
8 = 1/2 inch

Yes, 3/8 in dia. S/Stl tubing is hard to bend, you need 3 ft long handles to bend easily.

used 3/8 copper refrigeration tubing on mine easy to bend an looks pretty good troo west68

used 3/8 copper refrigeration tubing on mine easy to bend an looks pretty good troo west68

Copper fatigues easily and should never be used for fuel or brake lines.

I only needed 3/8 for my EFI swap, so I bought a new pre-bent 3/8" stainless line from Rick's, cut the hose barbs off, and used Swagelock compression to AN fittings.

Those are outside diameters, correct? I've wondered when told to run 1/2" if I should go with -10 rather than -8(?)

Tubing is referenced by OD.
Hoses are referenced by ID.

Codi - Why would you recommend hard lines over the flex lines which I assume are the braided lines, just curious. I would think that the braided lines would be real easy to run and route however you wanted. - Rob