Prior to installing the tank...
Prior to installing the tank we did the pump plumbing. A 90-degree fitting adapts us from 3/8 NPT to the proper flare fitting for our Aeromotive braided line.
Before installing the new Rock Valley stainless steel fuel tank we measured the depth of the tank and adjusted the length of the new Classic Instruments floatless fuel gauge sending unit before installing the unit in the tank. As of this writing, the floatless sending units are not available in an ohm range that would render our original gas gauge accurate. Because of that, we opted to mount a new Classic Instruments gas gauge in a traditional cluster under the dash. The floatless sender bolts up to the standard five-bolt flange, however if you have an original ’36-56 Ford gas tank they have a six-bolt pattern. The senders come in a several ohm ranges, check with Classic Instruments for your application.
We used a pre-formed fuel...
We used a pre-formed fuel line from Inline Tube to replace the old original. This piece is an exact duplicate of the original and saved us a lot of work.
The Aeromotive fuel pump was installed by Rock Valley so we began the plumbing to the fuel pump plate on top of the tank. Speaking of plumbing, our approach was to run hard lines for a majority of the fuel lines under the car, then using Aeromotive fittings we adapted to braided stainless steel lines for a flex connection to the fuel tank and the freshly installed Holley carburetor and Aeromotive fuel filter. The braided line up front starts at the Aeromotive inline fuel filter, making servicing the unit very easy. By using the flex line connection at the gas tank we did all the plumbing on top of the tank prior to installation, and then simply connected the flex lines to the hard lines after the tank was in place. This makes it simple to remove the gas tank in the future should the need arise.
Installing the new hard fuel lines involved using a pre-bent feed line sourced from Inline Tube while we fabricated our own return line from steel tubing. A flare to AN-6 adapter took us down to the braided hose and then the final connections were made. The stock filler tube was installed to the new Rock Valley tank using a new piece of fuel hose. It is important to use a piece of new fuel hose on this connection as the new hose is able to handle the modern gasoline blends without deteriorating.
Using a flaring tool we flared...
Using a flaring tool we flared the end of the Inline Tube supply line in preparation for the conversion to AN fittings.
The new tank is held in place with stainless steel straps supplied with the Rock Valley tank. When we did the test-fit it became obvious the fuel pump fittings were hitting the floor brace. A small cut-out was made in the brace and since we did not penetrate the interior floor there was no need to do anything else. A quick squirt of black paint prevented future rust and we were done with that small modification.
With the mechanical portion of the job out of the way we turned our attention to providing electrical power to our new fuel pump and gas gauge. The gas gauge has a long pigtail with a plug and since we decided to use an independent, underdash, Classic Instruments fuel gauge we routed the wiring through the car and passed the wire through the floor board using a rubber grommet in the newly drilled hole.
We produced a nice clean flare,...
We produced a nice clean flare, and don’t forget to put the nut and ferrule on the tube prior to making the flare.
The fuel pump was wired in similar fashion and the supplied relay was wired in and then the power was routed under the carpet rearward to the fuel pump, also passing through the floor board with a rubber grommet.
A double check of all connections and it was time to add some fuel to the new gas tank. A few gallons would be enough to supply the pump and test the system. With the ignition key on the Classic Instruments fuel gauge needle indicating we had fuel in the tank, and the Aeromotive in-tank pump was singing its happy song as it delivered the Aeromotive-regulated 3 psi of gasoline to our new Holley carb. It is best to have one person under the car and another operating the key for this first test, that way should you discover a leak the power can quickly be turned off, limiting any spill or danger. As it turned out our plumbing was leak-free and with a steady supply of fuel to the Holley carb the engine fired to life. Certain that all systems were working well, we filled the tank with some premium gas and enjoyed hitting the road knowing there was no chance of fuel-related problems for a long time to come.
We used a variety of Aeromotive...
We used a variety of Aeromotive fittings to build our braided stainless steel fuel lines at the tank and the firewall.
Cutting braided stainless...
Cutting braided stainless lines begins by wrapping the line with several layers of electrical tape.
A cut-off wheel makes quick...
A cut-off wheel makes quick work of cutting the braided-stainless and the Teflon tube within. The tape prevents the braids from unraveling.
Always use a coating of antiseize...
Always use a coating of antiseize when working with aluminum fittings, it acts as a lubricant to prevent galling of the threads.
Next we slip the nut over...
Next we slip the nut over the braided hose, if the electrical tape is too thick you may have to unwrap a layer.
The fitting is pushed into...
The fitting is pushed into the hose; this can take a little effort but be certain the fitting is completely seated in the hose.
Gently clamp the hose nut...
Gently clamp the hose nut in a vise and tighten the fitting into the hose. Take special care not to deform the nut with the vise.
While we know our Rock Valley...
While we know our Rock Valley tank is perfectly clean, fuel still must be filtered. We chose an Aeromotive inline filter to handle the job.
Since our new electric pump...
Since our new electric pump delivers well above the desired 3 psi for our Holley carburetor an Aeromotive fuel regulator was in order.
The regulator was mounted...
The regulator was mounted to the firewall with a liquid-filled fuel pressure gauge. The bottom port is the return line to the gas tank.
Once again an assortment of...
Once again an assortment of AN fittings were required to fabricate the return line. These fittings are from Earl’s Performance Plumbing.
The braided hoses were mounted...
The braided hoses were mounted with Adel clips also sourced from Earl’s. A single screw holds two clamps for a clean look.
The new Holley four-barrel...
The new Holley four-barrel carb was bolted in place and a piece of braided stainless line was connected to the fuel inlet with a hose clamp.
With plumbing complete it...
With plumbing complete it was time to handle the electrical connections. A relay was wired in place with a 10-gauge wire feeding the relay.
We opted to route the wiring...
We opted to route the wiring under the carpet taking care to avoid any sharp objects or potential pinch-points.
After drilling a hole in the...
After drilling a hole in the trunk area the wires for the fuel pump and the gas gauge sending unit were routed through a rubber grommet and connected to the top of the tank.
The new Rock Valley stainless...
The new Rock Valley stainless steel straps hang from the stock strap brackets.
Rubber pads between the tank...
Rubber pads between the tank and the straps prevent any chaffing of metal and with all our plumbing, electrical, and filler connections complete, we were ready for the open road.