Along with lockers and low-range gearing, having a fuel-injected engine is one of the best things for your 4x4 in terms of off-road performance. Your engine will just keep chugging at all angles—even upside-down. But what if your engine didn’t come with fuel injection from the factory? There are plenty of add-on aftermarket systems, but almost all start at around $1,000. Not the most expensive mod you can make, but not exactly low buck, either. And retrofitting a factory system from the junkyard can be complicated but not impossible.
We will be showing you a factory junkyard conversion soon, but if you are looking for a $20 carburetor option that will work almost as well as fuel injection now, it is hard to beat a Motorcraft two-barrel or Rochester Quadrajet four-barrel. The Q-Jet can be found on most GM cars and trucks made from the 1970s up until injection became standard. It is a spread-bore design, so if you have a square-bore manifold you will need an adapter. It is a great, dirt-simple upgrade for your small-to-large V-8, but most Q-Jets flow too much fuel for very small V-8s and almost all six- and four-cylinder engines. For smaller engines, Ford’s Motorcraft 2100 (or later 2150) two-barrel is a great option for a smaller carb that will run at all angles. Smaller engines will want to go with the 1.01-inch venture (size is stamped on the side of the carb body) that flows about 240 cfm. The 1.08-inch flows 287 cfm, while the larger 1.21-inch flows 351 cfm.
We have been pecking away at this 1971 CJ-6 for a few years now. The factory odd-fire Buick 225 sported a Rochester two-barrel that needed a rebuild, and the mechanical fuel pump had died. Not to mention that the factory under-tub fuel tank, lines, and hoses had all rotten away. In short, it needed everything replaced. Taking stock of leftover parts from other projects we had lying around, we came up with a 22-gallon Boyd Welding universal gas tank we had bought from Just Gas Tanks several years ago and a 1.08-inch venturi Motorcraft 2150 two-barrel carb off Hazel’s 1978 Cherokee Chief AMC 360 V-8.
If you are like us, you subscribe to the Summit Racing Equipment catalog and drool over all the shiny cool parts it offers. The Summit Racing Complete Fuel System Kit (PN SUM-PUMPKIT7A) includes an electric pump, a fuel filter, a fuel pressure regulator, 20 feet of -6AN braided steel fuel line, and enough straight and angled AN fittings and plugs to build a complete system. We browsed the offerings and found a Classic Industries universal fuel sender (PN SN39) that worked with our universal fuel tank and a TransDapt small-to-large, two-barrel adapter (PN TRD-2086) that could mate our small-pattern, two-barrel intake to the large-pattern Motorcraft carb. We will be wiring and firing this little engine pretty soon, but until then, check out our hillbilly fuel-injection build.
We had this 22-gallon Boyd Welding universal gas tank (PN 11019) from Just Gas Tanks left over from a previous project. It is a quality piece despite the $298.80 price tag. The tank came drilled and tapped for a standard fuel sending unit. Summit Racing Equipment had a Classic Industries universal fuel sender for $43.97 (PN SN39).
We followed the fuel sending unit is instructions to clock the sender inside the tank and adjust the float arm for full travel. With the rod properly adjusted and cinched down, we lopped off the extra material and installed the sender with the supplied gasket.
Intake manifold rat turds aside, swapping from the small-pattern Rochester two-barrel to the large-pattern Motorcraft carb is supereasy with TransDapt’s adapter kit (PN 2086), which Summit had in stock for $28.97.
The TransDapt adapter includes gaskets, mounting hardware, and of course the aluminum adapter. The supplied studs shown in the photo proved a bit too short after we figured in the thick Motorcraft 2150 factory gasket/spacer required for fuel bowl clearance on most manifolds, but we had some longer ARP studs in the shed left over from another project we were able to swap in.
We had previously removed the choke system since we knew we wouldn’t need it in sunny SoCal. We also swapped out the factory intake fitting with a -6 AN to 3/8-inch NPT adapter from Summit for $8.49 (PN SUM-220652).
For $305.07, the Summit Racing Complete Fuel System Kit (PN SUM-PUMPKIT7A) gets you 20 feet of -6AN braided steel high-pressure fuel line, all the plugs and fittings you need, and the pump, filter, and regulator you see here. The electric pump will flow 130 gph at 14 psi. The adjustable regulator can be set between 5 and 12 psi. We used Teflon tape to install the fittings before mounting them in the vehicle.
With the components mounted, you can turn your attention to building lines. Measure where you need to cut, and wrap the braided steel line with tape. Electrical tape is good, but we have had nice results with masking tape. As a plus, it doesn’t melt and turn gooey when you cut it.
There are many methods you can use to cut braided steel line, but for us the one we most often rely on is a very thin cutting disc in a 4 1/2-inch angle grinder. Make a nice, straight cut and take care to go fully through all the braid. The tape, if wound tightly enough, should keep the wire braid from separating and frizzing out.
What you are looking for is a nice, clean cut with no wire braid flaring out. Clean out any residual rubber from the inside of the line and then insert the hose collar over the cut piece of line, making sure you don’t booger up the wire braid as you go.
You will want the hose to come just up to the internal threads. Maybe just a little bit below. We normally hit the threaded portion of the fitting, especially the part that inserts into the hose rubber, with a little bit of lube before inserting it. Make sure you don’t force the line out of the collar as you go. As soon as you can get the threads to bite, go to your wrenches.
Special AN wrenches are available for purchase, but we have always relied on a pair of stubby wrenches from our trusty ol’ toolbox. Call us cheap. Tighten the fitting to the collar until snug, but don’t gun it down with the force of two gorillas arm wrestling.
We plumbed the rest of our fuel system taking care to avoid hazards and components that could rub the braided line over the life of the vehicle.
To be honest, we started half this install two years ago. Since then the fuel pump and filter have been in the back of the Jeep exposed to the elements. Aside from a bit of surface rust and dust, once we hooked up the fuel pump with a relay kit from Painless Performance (PN 50102) the system fired right up and purred like a kitten. Summit carries the relay kit for $44.99.