Technical Support - Electronic - Fuel Injector Manifolds
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Can I run a HILBORN EFI injector on a street car?

Because of EFI (electronic fuel injection), the Hilborn Injector has become the favorite choice for many types of motorsport enthusiasts that enjoy driving their cars on the street. This ranges from show cars that drive 500 miles a year to street rodders driving 35,000+ miles a year and everyone in-between. The joining of EFI and a Hilborn injector has produced what we feel is the ultimate induction system for any show car or street rod. We took the neck snapping throttle response, the increased torque and power, and the awesome engine acceleration common to a Hilborn Injector, controlled the fuel with EFI, and found we had an unbeatable combination of calm drivability and unmatched performance. But the best was yet to come. We found that our manifold design, which removes the distribution concerns associated with a common plenum, allowed even the most aggressive engines to have extremely good part throttle manners, while still retaining their aggressive exhaust note. Yes, that's right, our race inspired manifolds actually promote part throttle drivability (click for more info). This would be our most important benefit since you spend most of your time at part throttle in a street car. So not only is the answer, Yes, you can!, but for the perfect induction system, it has to be a Hilborn.

NOTE: Our products are not legal for sale or use on emission controlled vehicles.

What about a mechanical injector on the street?

A Hilborn mechanical injector is classified as a constant flow system and was designed to operate at WOT under load. As a constant flow system, pressure and volume are controlled by the main jet, or pill, along with pump speed (engine rpm) and nozzle size. The barrel valve, which controls idle fuel and transitional fuel from idle to WOT, can be compared to a ball valve much like the one that turns off the water in your house. The basic design and lack of fuel control of a barrel valve does not allow us to control the fuel at part throttle especially no load part throttle. If you consider the fact that an engine's fuel requirements are based directly on load, and that we can have many different loads at different rpms all at the same throttle angle, the lack of fuel control for street applications becomes apparent. A mechanical system does not employ enough fuel control in the operating range where you drive your street car and, therefore, is not recommended for street use.

Of course we have all heard the stories of mechanical system working on the street but few if any actually worked correctly. The use of a dial-a-jet, additional bypass valves, and home center ball valves have all been used to provide fuel control for adequate street use, but fall far short of the fuel control required as part throttle load is constantly changing. The constant manual adjustments needed, as one guesses the current fuel requirements of the engine, leaves very little time to actually drive the car and, at best, is incredibly inaccurate. Blown applications appear not to be as affected by the lack of fuel control of mechanical injection, possibly due to the load placed on the engine to drive the blower, but is still not recommended for those looking for the best all around drivability.

The use of alcohol helps because of it's large tune-up window, but fails to provide drivability due to loading up, mileage (in gallons to the mile) and severe oil dilution. Claims from those that run injected engines on stands or dyno's stating they can make mechanical injection streetable, are unable to simulate a fraction of the different part throttle load scenarios your engine will see, nor provide the required fuel control. Interestingly enough, engineers have devised a way to electrically control these valves and bypasses...it's called electronic fuel injection.