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Fuel Injection - Early Bronco TBI

Engine Fuel Injection Install Carburetor
Posted April 16, 2003

Bolt-On Fuel Injection for Your Pony

When speaking of four-wheeling, terms such as articulation, approach angle clearance, and suspension travel quickly become main points in the conversation. However, a vehicle's ability to conquer rough terrain is comprised of more than just suspension and tire size. Everyone understands the basic clearance issues, but what about the motor? Extreme angles can wreak havoc on a carburetor's ability to deliver fuel, and engine stumble isn't exactly desirable when you're in a sticky situation.

The answer is fuel injection, which is basically a computer-controlled, pressurized fuel delivery system that will not sputter and choke at elevation or at extreme angles. Pulling off that troublesome carburetor and converting to fuel injection will mean no more float bowls, better fuel economy, more low-end torque, better throttle response, and enhanced overall performance.

Early Bronco owners frequently have a difficult time trying to make the transition to fuel injection, so when we found out Turbo City has a universal TBI fuel injection system that works with the Bronco, we headed over to get the full story. Turbo City's fuel injection system is built around the GM '87-'95 throttle body setup and uses a coolant temp sensor, a Manifold Absolute Pressure (MAP) sensor, and an O2 sensor to monitor the engine's vital signs and make any necessary adjustments to the fuel and timing for optimal performance.

The stand alone kit includes a new or refurbished throttle body, a wiring harness, all the necessary sensors, all the necessary modules, a computer, a custom programmed chip, and an intake manifold adapter for your application. The Turbo City universal TBI is available not only for the Bronco, but also for other Ford, Jeep, and Toyota applications. It is a true Speed Density system and uses all the beneficial parameters of open and closed loop fuel injection.

The GM TBI system has a long-standing reputation for being nearly bulletproof in terms of reliability and construction, and coupled with Turbo City's 20-plus years of experience with retro-fitting it to work with other vehicles, this is a fuel injection conversion that is easily installed and one that will make your vehicle run better than ever. After a couple of modifications were made to the computer program to make up for the performance cam, headers, and aftermarket intake in our 351 Windsor, the Bronco fired right up. Cold starts are now no problem, and the throttle response is excellent.

One word of caution, though. If you and your Bronco (or Jeep, Toyota, and so on) are in any way subject to the kind of smog laws we have here in California, this kit will not pass inspection. You will almost certainly have no trouble passing the tailpipe test, but when the official pops the hood to perform the visual inspection, he's going to say the TBI is not original equipment and therefore not legal. Never mind that the vehicle runs better and produces cleaner emissions than the stock vehicle ever did. If your rig was built before 1974, you are fully exempt. Otherwise, check your state laws.

On a final note, we want to acknowledge the Ford purists out there for whom the idea of GM parts on a Bronco is anathema. We understand. However, four-wheeling can be a demanding pastime, and it makes no allowances for faulty vehicle performance. Throttle-body injection adapts readily to any four-barrel intake, it's easy to find parts for, and most any shop that knows GM TBI fuel injection can tune it. So while bolting that GM throttle body to your pony may raise some hackles, take solace in the fact that your rig will run better than ever, no matter how steep the incline or how high the elevation.


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  • The first item of business is removing the carburetor, linkage, and any vacuum lines. More than likely, your distributor has a vacuum advance line on it. The new computer will control the timing, so this line can be completely removed.

  • Because of the heater core and ducting in the Bronco, we decided the fenderwell was the best place to mount the computer. Turbo City used a second ECM shell to hide some of the external modules and the fuse box.

  • Pre-checking the wiring layout before installing sensors or modules ensures your install is easy and clean.

  • A billet four-barrel intake manifold adapter fits the TBI unit to the intake. Note that we mounted the MAP senor on the backside of the intake.

  • The kick-down cable for the C4 tranny was reinstalled just as it was on the carburetor.

  • The ignition control module translates the distributor's pulses and alters the timing. You must use a magnetic pickup-type distributor with this system, and the advance must be locked down with the proper phasing. The instructions explain this in great detail, but if you ask, Turbo City can make the necessary adjustments to your distributor.

  • Ford C4 transmissions use a special kick-down linkage. You can either use the original one off of the carburetor or have Turbo City fabricate a linkage to fit your application.

  • Three bolts hold the throttle body to the adapter plate. With those tightened to spec, the linkages can be checked for functionality.

  • Finding locations for sensors is easy. The instructions give good advice on their strategic placement.

  • An electric fuel pump is required for the fuel injection. A return line back to the tank must be installed as well. You can run the return line to the back of the pump, but it is not advised because it will most likely cause vapor lock.

  • Turbo City's fuel injection system comes with a bung to weld to the exhaust. You don't need to weld it in the header, but it needs to be as close to the collector as possible.

  • Locking out the distributor advance and setting the distributor phasing can be tricky, but, again, Turbo City's instructions will guide you through. It is best to convert the distributor's pigtail to the Turbo City ignition module plug for a corrosion-resistant connection.

  • Install the fuel lines and the vacuum lines on the throttle body.

  • Run your wiring loom and connect the harness to the sensors.

  • Plug in the injectors and give the whole installation the once over. Make sure all connections are good and all fuel lines are tight.

  • With the system ready to go, turn on the ignition and watch for any fuel leaks. If all is well, fire it up. The injectors will pulse fuel and should fire right up. Make sure you go through the ignition timing setup per the instructions.