EFI H.O. 5.0 Engine and Cylinder Heads

Categories: Cylinder Head Tips

When discussing the highest performing engines of the past few decades, the EFI H.O. 5.0 engine consistently comes out as one of the top options. When Ford added EFI to the 5.0L H.O. engine that was already on the market, they may not have realized the massive change they would make to the industry. Today, we’re going to head back in time to learn about the history of the Ford EFI 5.0L H.O engine, corresponding cylinder heads, and the revolution it caused.



History of the EFI H.O. 5.0L Engine

Ford initially added EFI to the 5.0L H.O. engine it offered back in 1986, which provided a very powerful addition to their Mustangs of the time. H.O. stands for high output, but Ford fanatics were always looking for an engine with better performance.


The original Ford 5.0L engine was introduced in 1978, which was a continuation from the Windsor V8, but this time using the liter addition in the name. However, it didn’t gain much attention until it was added to the Mustang GT four years later in 1982. These original engines offered a 2-barrel carburetor and 157 horsepower.


While this doesn’t sound like a great offering to us today, keep in mind that this was a big step up from the options offered in the 1970s. As the company proceeded to upgrade the cylinder heads and make other tweaks to the engine over the years, it only continued to gain interest within the industry. Finally, 1986 saw the addition of electronic fuel injection (EFI), and the start of a new era commenced.



More Torque and Vehicle Power

When EFI was added to the engine, it offered drivers increased torque and good power. One surprising fact is that the horsepower was reduced by 10 in the initial launch of this engine, which made some drivers dubious about the new engines, particularly if they were looking to modify the engine in the future. However, as changes were made by Ford as time progressed, the horsepower increased once again. Electronic fuel injection strives to replace the need for a carburetor that will mix fuel and air. Instead, it directly injects the fuel into the engine’s manifold with electronic controls.



Benefits of EFI

There were many reasons why Ford opted to add EFI to the engine at this time, and it offered many benefits to drivers around the world. If you had previously been frustrated by struggling to start your vehicle, then EFI often eliminated this issue. It can work with both hot and cold starting, which is one of the biggest challenges with smaller engines such as this one.


Emissions are reduced with the EFI engine option, as it offers better accuracy than with a typical carburetor engine. Drivers also noticed that their Mustang or other Ford vehicle required less maintenance over the years, saving them time and money. This type of engine could even help to extend the life of the vehicle, which is why it helped to boost the afterparts industry so much. That being said, repairs to the EFI H.O. 5.0L were certainly costly, and that’s something to keep in mind when upgrading any engine or cylinder head.


EFI works to offer more consistent power, allowing drivers to enjoy good horsepower no matter the road conditions. It reduces the guesswork that’s often required to find the perfect settings and conditions for the vehicle, which is why many people opted to upgrade their vehicle with the EFI H.O. 5.0L engine. Finally, fuel efficiency is greatly increased, with an up to 25% improvement on the previous model. This efficiency is beneficial for everyone and it’s why this technology is still so incredibly popular.



Ford Small Block Engines

This engine falls within a group of engines that Ford produced from 1961 until 2000, which were designed to succeed the Ford Y-block engines. Over the years, these engines were used within the Mustang, Mercury Cougar, Ford Falcon, and Ford Explorer, to name a few. From 1991 onwards, the company worked to phase in the Modular V8 engine in replacement of this collection of engines. You may hear the engines referred to as the Windsor by many Ford enthusiasts, although this was never a name given to the line by the company. In fact, it was just a term used to refer to the location where the engines were manufactured.



A Powerful Engine for the Ford Performance Era

In 1987, the EFI H.O. 5.0L offered 225 horsepower, kick-starting the performance movement for the company during this decade. Manufacturers soon noticed the benefits of this engine, so the number of engines and cylinder heads produced around this time increased significantly.


Ford also went on to create their Cobra engine, which offered the features of the EFI 5.0L H.O. and the GT-40 induction parts. Later on, Ford would go on to improve this engine with the Ford Modular Motor, but that doesn’t take away from the huge impact this engine had on the market at the time. It made the Mustang Fox a high-performing vehicle option and brought the aftermarket parts industry back to new life. It’s still an affordable option for many drivers and offers many benefits for anyone looking to upgrade their vehicle with it to this date.



EFI H.O. 5.0L Engine – Conclusion

The EFI H.O. 5.0L engine worked to transform the aftermarket parts industry after its launch and is still one of the most popular engines of the past few decades. With the addition of EFI after the introduction of the original engine a few years before, drivers were keen to improve the power and performance of their vehicles with this upgrade.


Ford continued to make adjustments to the engine over the years, offering the best product possible for drivers of many different models from Ford. It provided an affordable upgrade for vehicle owners who were looking to experience the benefits of EFI for themselves, and it helped to pave the way for many of the top-performing engines that are still popular with drivers worldwide today.



Cylinder Heads for EFI H.O. 5.0L Engine

Are you an owner of a Ford vehicle with an EFI H.O. 5.0L engine? If you would like to replace the cylinder heads on your vehicle, then please call Clearwater Cylinder Head at 1-800-572-1963. By providing us with your Ford VIN number and a casting number, we can help you identify options for cylinder head replacements. We sell both new and refurbished cylinder heads, and we have one of the largest inventories of cylinder heads in the United States.


“Overall a great experience with Clearwater Cylinder Head.  Every time I called with a question after ordering they picked up the phone, and were helpful and pleasant (rare these days).  My cylinder head arrived at my door 2 weeks after my order which is exactly as promised.  The head was packaged well and there was no damage from shipping.  The head was remanufactured (as expected) and all surfaces were super clean, all holes were tapped clean and the valves looked great.”

– Ryan Edwards