Subscribe to Precision Engine
Sign up for our E-newsletter
Routing the plug wires in aluminum tubing for this custom engine was simply an exercise in “being different.” The tube nuts and sleeves that meet the spark plug boots are for cosmetics only (the nuts and sleeves are epoxied in place).
Straight 3/8-inch tubing runs from the fuel log to the carburetor inlets. Since I wanted to color-coordinate this build, I had all of the tube nuts and tube sleeves anodized in a violet color at a custom anodizing shop.
This custom street rod engine takes full advantage of metal tubing for all of its fuel and vacuum plumbing.
I even hard-plumbed the PCV valve, again using 3/8-inch tubing a -6 tube nuts and -6 adapters.
The hard fuel line is rigidly mounted from the mechanical fuel pump to the carb. Here the hard line, equipped with a -6 tube nut and sleeve, attaches to a -6 90-degree adapter that features a male -6 flare for the tube nut attachment and a female -6 at the opposite end to mate to the -6 male adapter fitting on the pump (the fuel pump inlet fitting is capped here using a -6 sealing cap while the engine was on display).
The fuel feed for this engine features 3/8-inch aluminum tubing. A three-way -6 male adapter allows fuel transfer from the pump to both carb bowl inlets. A 90-degree male/male -6 adapter connects the main tube run to the rear carb bowl.
This hard-tube plumbing setup was made for nitrous feed to a Honda engine’s intake manifold runners. This setup features -4 AN tube nuts/sleeves. A bit of patience and a hand-held tubing bender was all that was required to achieve a neat and symmetrical tubing layout.
Hand-held tubing benders are readily available. This inexpensive bender (from Rigid Tools) is one of the nicer hand-held benders I’ve used.
Before bending the tube-and definitely before flaring-remember to slip the tube nut and tube sleeve onto the tube. If you forget, you’ll need to cut the tube and start over.
With the tube bent and flared, and with the tube sleeve and tube nut in place, the assembly is ready to thread onto a male AN fitting.
This nitrous oxide plumbing setup features 37-degree cone jets that mate to the tube flare and the tube sleeve.
Tags: BENDING AND FLARING, HARD LINE PLUMBING, PLUMBING, TUBE NUTS AND SLEEVES
