Photography: Ed Taylor
Converting from a carburetor to electronic fuel injection (EFI) has always been a bit of a hassle. The number of sensors and the miles of wiring harness, not to mention learning how to tune the sometimes confusing control unit with a laptop, scare a lot of people right back to their carburetors. But FAST's latest creation changes all that and uncompli-cates EFI. The EZ-EFI is said to be self-tuning.
If you can install a carburetor, you can install the EZ-EFI kit. The spine of the system is a four-hole throttle body that has a standard Holley 4150 flange, so it'll bolt to any intake manifold that a Holley will. The heart is the computer that controls it, and you don't have to hassle with programming—the computer learns what the engine wants and programs itself. And finally, the wiring harness isn't even that complicated; all but four wires connect to the throttle body itself.
Probably the most difficult or time-consuming part of the entire installation is upgrading the fuel system. EFI must have high fuel pressure to operate, so an electric EFI-style pump and return system must be used. FAST has an EZ-EFI fuel pump kit and a hose and fitting kit, and we highly recommend using both for simplicity's sake.
To see just how this system works, we tested it on two engines at Duttweiler Performance, one a 496ci big-block
Chevy and the other a 350. The same EZ-EFI system was used on both engines to gauge its ability to tune itself, and the only thing we had to change was inputting the specs for each engine into the included handheld controller. On both engines, the system fired right up and settled into an idle, and its self-learning function caused each engine to pick up a little more power after a few pulls on the dyno. Surprisingly, it actually made a tad more horsepower on the small-block when compared with a Holley 750 carburetor.
The main appeals of entry-level electronic fuel injection are efficiency and ease of starting, so to gauge them, we installed the same unit in a car and tested it.
Larry Abel's '65 Malibu SS was the guinea pig, and McMillan Speed and Fabrication did the work. The EZ-EFI system replaced the restored Rochester square-bore carburetor on the very mild small-block, but before that, we tuned the carb as well as we could, then took the car on a 100-mile mileage loop. The carb delivered 13.2 mpg. With EZ-EFI, the exact same mileage loop brought home 18.5 mpg.
So there you go—FAST's EZ-EFI is a bolt-on that works, goes on easily, returns better fuel mileage, and in some cases might squeak out a few more horsepower. When it comes to electronic fuel injection, it just doesn't get any easier.
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