K&N Electronic Carburetor Injection: Modern Performance for Your Classic Ride

Holy mackeral, guys. Today’s topic has me so excited that I truly don’t know how to start this article in a professional manner.

K&N, the world’s leading manufacturer of washable performance air filters and air intake systems, offers a state-of-the-art electronic carburetor injection system. This product breaches such a major gap between fuel injection and straight carburetor that I DON’T UNDERSTAND WHY MORE PEOPLE AREN’T TALKING ABOUT IT.

Every once in a while, the industry is graced by a product that seems to redefine what is and isn’t possible—and suddenly, the standards change. In my eyes, the K&N Electronic Carburetor Injection, or ECI, is exactly that product, and lot of us—including myself—will be taking full advantage of this unit.

Okay, so what is ECI??

Electronic Carburetor Injection sounds like a contradiction, right? Well, here’s the skinny. K&N’s ECI is a bolt-on, supplementary fuel delivery system that works with a carbureted vehicle. Depending on the selected model, an injector or two are added to the base of the carburetor which squirts additional fuel as needed.

“Traditionally, achieving an easy cold start required aftermarket EFI systems—which are often prohibitively expensive, time-consuming to install, and confusing to tune,” says K&N. “In a way, the ECI system works like an EFI system … but [in this case] the engine is still fed primarily by the carb. The ECI acts as a supplement to your existing carbureted setup, rather than a complete replacement system such as EFI or TBI.”

Basically, fuel injection systems use a throttle body with fuel injectors as the primary source of fuel to the engine. As the engine runs, the ECU and O2 sensors work to send the right amount of fuel to the engine as the throttle is pressed. The K&N Electronic Carburetor Injection works as a supplementary fuel source leaving the carburetor to do the bulk of the work. As you run the engine, the carburetor will deliver as much fuel as you set it to. But an O2 sensor is in place on the exhaust, so that as the engine runs lean, the ECU directs the injector to supply the amount of fuel the engine needs to run right.

So, K&N’s ECI doesn’t add fuel mechanically. It’s computer-controlled with an ECU, much like traditional EFI. Better yet, the system itself only consists of a few working parts and anyone with an understanding of a fuel injection system will see how this can be quite effective.

The way this system works is ingeniously simple.

Injectors are mounted to the engine beneath the carburetor with the use of a 1-inch spacer. This spacer mounts just like any other carb spacer you would fit to an engine, except it is built to accommodate 1-2 Bosch 30lb injectors. (The kit for Holley 4150 or Quadrajet-style carbs mount one and the Holley Dominator setup runs two.)

These injectors are tied to the ECU with a wiring harness. A harness is also present for the O2 sensor that is fitted to the exhaust system. Of course, you will need a source of fuel; to do so, you just tap into the existing fuel lines.

With this set up correctly, the K&N Electronic Carburetor Injection is able to provide the engine with the additional fuel needed for optimum engine performance.

Tips and Installation

I can hear the wheels turning in your tech-savvy brain from here, which means you’ve probably already figured out when this system will be the most helpful: cold starts and wide-open throttles.

And really, for the price (roughly $500), it’s so worth it. Plus, with the K&N Electronic Carburetor Injection, you can also create all-around performance gains.

We all know that tuning carbs can be a chore. In fact, even the most experienced tuners struggle to set one up so that it never runs lean or rich at one point or another. Mainly, this is because of the limitations of a mechanical setup—it can’t react and adjust to the rich or lean readings as they occur. But since the ECI is a supplementary fuel system, its job is to provide the engine with additional fuel as needed.

So, if you create an environment where fuel is always needed—i.e. create an engine that runs lean—you would constantly have this system working to bring the engine to the exact ratio. It will supply the engine with the right amount of fuel at all times.

Installation-wise, aside from the jets, K&N provides you with everything you need to set this system up and run it right out of the box.

It includes a spacer, fuel injector(s), the ECU, wiring harness, and the O2 sensor. K&N even supplies the hardware and gaskets needed for mounting the spacer to the manifold.

The oxygen sensor is a weld-in style, which makes installing it the most complicated step in the process. (K&N has mentioned possibly including a clamp-style O2 sensor in the future.) How can this be possible with a fuel injection-style system, you ask? Because the K&N ECI is working off the existing fuel system. There’s no swapping fuel tanks. No new sending unit. Hell, you can even run a mechanical fuel pump and this system will still perform.

And for those who want to make adjustments, you can tap into the system and adjust the settings. Want a laid-back economical tune? Sure. Want to make an aggressive tune? Go for it. You can even swap out the injector if you want. That’s right, it’s a Bosch 30lb injector and you can swap it out with whatever you want.

The K&N Electronic Carburetor Injection is truly amazing when you take into account all that’s being made possible with it.

Who is ECI right for?

If you’re reading this wondering why you should bother with this upgrade when fuel injection gets more affordable every day, let me make a case for the budget builders out there. The most affordable fuel injection systems are still going to run around $1,000. And that’s before the cost of the fuel system upgrades you need to run them. For the guy with a carbureted vehicle, who wants better performance at an affordable price, this system is a great solution. It’s also great for those who might have the cash but can’t justify spending it on a car they only drive on the weekends.

Plus, we can’t forget about the purists. The guys who just don’t feel right adding space age technology to their classic car. And while this system is pretty darn innovative, those guys still have the comfort of looking you dead in the eye and saying their car is carbureted. Because, truthfully, it is. (It just has a unit helping it achieve modern performance.)

Performance enthusiasts have also been known to stand with carburetors, as they feel that you just can’t top the performance at wide open throttle in the same price range. K&N’s ECI helps them reap the rewards of the performance they can afford, while still having an engine tuned to work at all RPMs.

Really, guys, I can make a case for this all day. In my opinion, the list of who this product is applicable for just keeps going and going.

So, why is this just now coming up??

K&N dropped this new ECI system over a year ago, yet it doesn’t seem to be drawing the level of buzz I’d expect. I can only assume that the plummeting cost of fuel injection systems has overshadowed the sheer brilliance of this product. It hits so many points in terms of usefulness and effectively breaches the gap between fuel injection and carbs.

And, I’m telling you, as far as anything I’ve come across in my years spent in the industry, this is the most affordable way to bring your carbureted engine up to modern performance standards.