1972 Chevy Nova LSX Engine Swap - Modernized!

Most LS engines have a fuel return line coming out of the intake manifold. Ours didn't. We later learned that '03-and-up 5.3Ls didn't have one. Fortunately we were advised to use a '99-and-newer Corvette fuel filter. These are an inline regulator/filter combination with a return line built in. By doing this, we replaced the filter supplied in the conversion kit and made our install even easier, since we didn't need to run a return line through the length of the chassis.

Dorman makes a fuel line repair kit that comes with factory-style fuel hoses and the tool to install the factory-style quick-disconnect ends. We used a combination of this and hard-line to run the new fuel line to the engine.

Admittedly, trying to figure out what headers work on a conversion like this can be a nightmare. Rather than guess, we went directly to Sanderson Headers and were shown a direct bolt-in performance header (PN LS150) with 1 1/2-inch diameter primary tubes with a 2 1/2-inch collectors for our application. Sure enough, everything cleared and fit like a glove.

Next on the list was to install the Turn Key harness. This simple plug-and-play harness may look intimidating at first, but it's well labeled and pretty easy to follow. The first thing to be addressed is mounting the computer, relays, and fuses. For this combination, we mounted the computer onto the firewall, right above the heater box. For the relays and fuses, we mounted them on the passenger-side fenderwell.

Once the computer and relays were mounted, we plugged the harness into the corresponding plugs on the engine. The harness also includes two O2 sensors, but requires O2 bungs to be welded directly into the exhaust. It's worth noting that our conversion kit even came with a K&N filter, but we weren't able to take advantage of it with the truck intake and accessories. Instead, Stoker plans to modify and reuse the factory intake ducting.

There are three relays in the harness, two for electric fans and one for the fuel pump. Realistically, we only needed the fuel pump relay; however, we went ahead and mounted the fan relays, giving us the option to use them down the road. All that's left is to run the power wire to the battery and accessory power for the computer and fuel pump.

Since we did away with the drive-by-wire assembly, we used a Lokar LS throttle cable. To install it, we used the supplied cable bracket from Turn Key and hooked it up to the stock pedal.

Finally, Stoker was able to move on to the little things to get this the mill up and running: the battery, power steering hoses (if applicable), shift linkage, adding fluids, and hooking up the car's factory wire harness to the starter and alternator for power. With the vacuum hose connected to the brake booster, it was only a matter of finishing up the exhaust.