Professional Products Powerjection III EFI System - 1970 Chevy El Camino

Our experience confirmed just how easy an installation can be, plus the kind of performance and/or economy gains that can be achieved. The vehicle we chose was a '70 Chevy El Camino SS 396 with cowl-induction. The vehicle had a spreadbore carburetor, which created a few additional challenges but nothing that wasn't easily handled. The El Camino had a few modifications such as a Street Performance aftermarket manifold, an Edelbrock 650-cfm carburetor, a Crower street cam with 276-degrees duration and .518-inch lift, plus headers.

The Powerjection III comes with "Self-Learning" software installed into the system that's suitable for the vast majority of vehicles. This means as you take your car out for a spin it will essentially self-tune itself for optimum performance. Only engines with radical modifications will need laptop tuning, and even in such a case, the Powerjection III is much easier than other systems. We connected a laptop to the EMS, loaded in the Dashboard Software and let the Wizard go to work. You can also go in and individually do any type of programming or mapping the same as you would with any other aftermarket EFI system. Take a look at how we easily updated and upgraded a big-block Chevy with new fuel-injection.

After we removed the air cleaner, we disconnected the linkage, and unbolted the stock carburetor.
After we removed the air cleaner, we disconnected the linkage, and unbolted the stock carb
Because this was a spreadbore manifold we used an inexpensive Professional Products adapter plate (#52111) to accept the Powerjection III throttle-body. Next up, we installed the supplied 1/4-inch thick gasket and heat isolation spacer and then installed the throttle-body.
Because this was a spreadbore manifold we used an inexpensive Professional Products adapte
The throttle-body had a few wires that came out of the EMS. One went to the negative side of the coil. Another wire goes to the ignition switch; one goes all the way back to the fuel pump, and the final one connected to a 12V power source. No ground was required as the unit is self-grounding once it is bolted to the manifold.
The throttle-body had a few wires that came out of the EMS. One went to the negative side

On this installation, the pipe threads on the supplied temperature sender were smaller than the pipe tap in the manifold, so a pipe thread reducer was required.
On this installation, the pipe threads on the supplied temperature sender were smaller tha
It is best to screw the sender into the reducer, using some thread sealant, and then screw the assembly into the manifold. If you act fast, only a minor amount of coolant will be lost, which can easily be topped off. This avoids having to drain the coolant. We then connected the lead from the EMS to the temperature sensor.
It is best to screw the sender into the reducer, using some thread sealant, and then screw
We then threaded the O2 sensor lead from the throttle-body down to where the sensor was installed into the exhaust pipe. Then, we clicked the two connectors together.
We then threaded the O2 sensor lead from the throttle-body down to where the sensor was in

We were now ready to connect the throttle cable to the throttle-body linkage. Because this was a spreadbore setup, in order to connect the stock throttle linkage, one of the holes in the throttle body linkage arm had to be enlarged with a drill.
We were now ready to connect the throttle cable to the throttle-body linkage. Because this
The stock mechanical fuel pump was unbolted from the engine and a fuel pump block off plate was installed. We made sure to remove both the inlet and return fuel lines from the pump before unbolting it.
The stock mechanical fuel pump was unbolted from the engine and a fuel pump block off plat
The supplied fuel filter was then spliced into the fuel delivery line from the tank and a short piece of hose was needed to connect the filter to the inlet fitting of the throttle-body.
The supplied fuel filter was then spliced into the fuel delivery line from the tank and a

Another section of hose runs from the fitting on the bottom of the pressure regulator down to the return hose that was disconnected from the stock fuel pump. The installation was now complete.
Another section of hose runs from the fitting on the bottom of the pressure regulator down
After the installation was complete, we turned the electric fuel pump on and checked all fuel line connections to make sure there were no leaks. It was now time to fire up the engine. In the case of our El Camino it immediately fired, but needed a slight screwdriver idle adjustment. The fuel pressure on the supplied fuel pressure regulator was checked and met the recommended pressure of 43-PSI. After driving the vehicle for 20-30 minutes the self-learning software had our engine purring and ready to run hard.
After the installation was complete, we turned the electric fuel pump on and checked all f