Cross-Ram EFI: A Chevy Icon Gets Modern Performance

When it comes to iconic small-block Chevy performers, the legendary cross-ram equipped, small-block Chevy engine is a top contender in both performance and style points. EFI innovator Fuel Injection Technology (FiTech) has been providing do-it-yourself EFI products that are engineered to bring the benefits of today’s EFI to vintage automobiles. This latest offering features cross-ram EFI with dual, four-barrel throttle bodies. This is the perfect solution for Bowtie enthusiasts who want modern drivability that can only be achieved through fuel injection, and also make a statement every time the hood is raised.

We’ve been doing some upgrades on our 1964 Chevelle lately. Some of the work, such as adding a new Tanks Inc. fuel tank, was in preparation for plans we had for the car. Adding the FiTech Ultimate Sync Dual Quad EFI system and Offenhauser cross-ram intake is the reason we upgraded to an in-tank, electric fuel pump. During the tank install, we also ran new pressure and return hoses from the tank to the front of the car. From there, we were able to use one fuel pressure regulator that would then feed both of the throttle bodies on our new, awesome-looking induction system.

The foundation for this install is that iconic Offenhauser cross-ram intake. The Offenhauser low-profile, dual-ram intake base, Offenhauser low-profile, dual-quad top plate, and throttle linkage are available as a kit from FiTech (PN: 92200). To make the EFI conversion as simple as possible, we ordered the entire 2×4 EFI conversion kit (PN: 92211), which includes FiTech’s 500-horsepower, dual-throttle-body system along with the upper and lower intake sections and linkage. This kit also requires the use of FiTech’s Dual Sync distributor as well. We also opted for great-looking ARP 12-point bolts to hold the intake to the heads, secure each throttle body, as well as mount the dual-quad top plate to the intake base for a super-clean appearance.

We love the fact that we can work together with a company such as Offenhauser and put our modern touch on a classic design. – Mike Wahl, FiTech

FiTech offers either black or gold throttle bodies with three different injector sizes to supply engines in 500-, 750-, and 1,000-horsepower configurations. Previously, our torquey 383 churned out 442 horsepower at 5,400 RPM and 476 lb-ft of torque at 4,100 revs. We opted for the gold 500-horsepower duo of throttle bodies to bring modern performance to our Chevelle. If your engine requires more fueling, simply contact FiTech, and they can direct you to the perfect system for your application.

Each FiTech four-barrel throttle body utilizes its own Idle Air Controller (IAC), oxygen sensor, and necessary wiring to the system’s stand-alone ECU. The harness for our application features all terminated connections, making this a true plug-and-play installation.

Each throttle body supplies fuel according to one of the two wide-band oxygen sensors wired to the ECU. Each sensor controls a specific bank of the engine. Since this is a cross-ram design intake, the driver’s side O2 sensor controls the passenger’s side throttle body and vice versa. The ECU controlling the fuel through our way-cool cross-ram EFI system is FiTech’s LS-based control unit, which can also control 4L-series electronic transmissions. Our Chevelle has a non-electronic 700R4 self-shifter, so only a TV cable will be necessary for our application.

Modern Performance For Our Cross-Ram

As mentioned, Chevy’s cross-ram intake is an iconic design, known in racing circles as a true powerhouse. The addition of the FiTech EFI system to this design only adds to the package with modern performance, improved fuel mileage, and reliable cold-starting, as well as easy tunability through the system’s hand-held interface.

Once installed, we only needed to input our engine’s configuration per the initial setup video above, to get our FiTech dual-four-barrel, cross-ram EFI induction system up and running. From there, the system uses input from each of the wide-band oxygen sensors to trim the fuel precisely for each bank of the engine.

The finer points of our install are easily done with just the push of a few buttons. We can further adjust the air/fuel ratios of our engine’s diet of fuel, adjust the “accelerator pump” for better performance, and enable fuel-shutoff to preserve each drop of fuel. We can even increase the key-on initial shot of fuel, which will help compensate for the cross-ram’s lengthy runners. No pedal-pumping or choke is necessary.

You also need to control timing to get the most performance and fuel mileage possible, and we opted to use FiTech’s Dual Sync distributor (P/N: 99565) with the accompanying FiTech Go Spark CDI + Go Spark Coil (P/N: 91100) and FiTech 8mm spark plug wires (P/N:90022). This combination allows us to electronically control timing in conjunction with our fuel sipping. What’s more, the Go-Spark CDI produces a series of multiple sparks below 2,500 rpm to further improve starting, idle quality, and throttle response.

Installing The 2×4 EFI System

Thanks to the cavernous under-hood space of our ’64 Chevelle, installing the FiTech cross-ram EFI system wasn’t complicated, but there are a few things specific to installing the system. Mainly, that Offenhauser intake is a lot wider than the factory, single-four intake. You need to make sure there is sufficient clearance at the valve covers.

We used the threaded port on the right front of the intake to feed the brake booster for our car, so our power brakes would work properly. We also needed to move the oil pressure sending unit to the oil gallery port at the front of the engine for sufficient room. It is also important to make sure the oxygen sensors are connected properly, keeping in mind that the driver’s side sensor directs the fueling of the passenger’s side throttle body.

We were pleasantly surprised at the amount of clearance we had between the hood and the throttle bodies after checking with some soft putty. Even with the air filter installed, we have no worries of making contact with the underside of the hood under acceleration. One area that did require some fabrication was building a linkage from the pedal arm to the throttle linkage on the intake.

The Benefits Of FiTech’s Cross-Ram EFI

As cool as this system looks when you open the hood, we like the way it transformed our torquey stroker engine into a mile-eating, highway hauler. The mid-range torque of our 383 is amazing. The car has had several different carburetors over the years and now, with the long intake runners of the cross-ram design, has much more torque than anything it’s had previously.

The true beauty of the cross-ram EFI is that adjustments can easily be made, and the system tweaks the engine’s operation as you drive. The hand-held controller allows you to make a broad range of adjustments to optimize the system to your application. Once any changes are made, you can leave the controller connected or unhook it for out-of-the-way storage in the glove compartment or console.

You can also hook this system up to a laptop for better viewing of the various charts and fueling tables if you wish. We’d say that FiTech’s engineer, Jeremy Schmidt, has done a great job of making everything accessible via the handheld device, so a laptop is not necessary. There are also plenty of helpful videos on FiTech’s YouTube channel for insights into a myriad of topics. FiTech also provides clear and concise instructions with each kit, explaining each step during the installation.

As of this writing, we’ve had the system on the vehicle for a couple of weeks. Just driving around town, we can notice the system honing the fuel trims to perfection. We’re looking forward to putting some highway miles on the Chevelle, but as yet haven’t had the chance to drop the top and hit the open highway.

While carburetors have served us well over the decades and will continue to do so for the foreseeable future, fuel injection does have its advantages. The fact that these advantages are now available in a cross-ram EFI package just makes this upgrade so much cooler. Modernizing all the coolness of those iconic small-block Chevy engines has truly come of age!