Best Ford F-100 Engine Swaps

Ford’s F-100 pickups, made from 1948-1983, are great candidates for a variety of builds. As classic pickups, they make great restoration candidates. But with a few upgrades, it’s also possible to turn your F-100 into a powerful ride.

Whether you’re looking to restore or trying to go full hot-rod, you may need to perform an engine swap. For F-100s that are good restoration candidates, a new era-appropriate engine may be needed to get the wheels turning again. For daily drivers, an engine upgrade can bring some modern comforts to your ride. And for those focused on creating a total powerhouse, a modern engine swap can add a lot of horsepower.

There are several engine swap options for F-100s that can address all these goals.

F-100 Engine Comparisons

With enough money and time, you could probably make almost any engine swap work. However, some engines are particularly good candidates due to brand compatibility, size, and the availability of swap parts.

Brand compatibility is fairly self-explanatory. All other things being equal, you’ll have an easier time swapping a Ford engine into a Ford vehicle. It also tends to be less expensive, since there will be more parts you can reuse.

The size of the engine is also relevant. Like most classic vehicles, the F-100 came with an overhead valve, or pushrod, style engine. These engines are significantly smaller than modern overhead cam engines.

It’s possible to swap an overhead cam engine into a vehicle that didn’t have it originally. But it may require relocating some vehicle components like the battery. This type of change can make an engine swap more time consuming and expensive.

The popularity of an engine swap usually indicates that it's easier to get the extra parts you'll need. LS swaps and Coyote swaps have tons of parts already made for them. Less fabrication and more availability makes a swap a lot easier.

Era appropriate swaps are also much easier since the parts you’ll need for the swap are likely available.

Era-Appropriate V8 Swaps

Through the F-100’s generations, it used a variety of Ford engines. Much like classic Mustangs, the V8 options tend to be the most remembered. Most production F-100s came with a six-cylinder, though. Often, these six-cylinder F-100s are the best candidates for restoration. Not only were they likely not driven as hard, but they’re also less expensive.

One of the most popular engine swaps for F-100s is simply to select an era-appropriate V8. Obviously, this has the advantage of addressing every engine swap consideration. There’s brand compatibility, good size, and plenty of parts to help make the swap a reality.

Some F-100 owners opt to swap in a different V8 than the one their F-100 came with. This is most often done with the engines that weren’t used for very long and are difficult to find parts for.

Though there were many different V8s used in F-100s, we can break them down into three basic families.

Y-Block V8

The Y-block V8 engine was used from the early 1950s through the early ‘60s. This is a relatively short lifespan for a V8. Though the Y-block was ahead of its competitors in terms of displacement, torque, and horsepower, it was also very heavy.

The short lifespan means that it's difficult to find Y-blocks in good condition, and even more difficult to find parts for it. This era-appropriate V8 swap is possible but challenging. Some maintain it’s worth trying just for the unique functioning of the Y-block V8.

Windsor V8

Starting in 1961, Windsor engines became the small block V8 of choice for Ford vehicles. It was such a great engine that it continued to be in use through 2001, and modern Windsors are still available today.

Windsor V8s came in a variety of displacements, ranging from a modest 221 CID to a robust 351 CID. The most popular was the 302 CID, or 5.0L, version.

Because of how long they were used, and how many vehicles they were put into, it’s easy to find parts for Windsors. It’s also easy to find junkyard Windsors. They can be dug out of Fairmonts, Mustangs, Thunderbirds, Capris, Cougars, and many others.

This is one of the most popular V8 swaps for F-100s.

FE V8

The FE is the natural evolution of the Y-block. Unlike the Y-block though, it’s much easier to find an FE engine in good condition. FE’s were produced from the late ‘50s through to the late ‘70s. The FE line also includes the “FT” engines. FT (short for Ford-Truck) engines were designed for heavy-duty vehicles and used steel crankshafts.

Unlike the Windsor, the FE is considered a “big-block” engine. Despite the name, FE engines were available in a wide range of displacements, starting at 330 and growing as large as 428 CID.

These engines could be found in many vehicles. They were used in F-series trucks, but also in the Thunderbird, the Fairlane, the Mustang, the Torino, and a variety of other vehicles.

Restomod Engine Choices

If you couldn’t care less about era-appropriateness, then there’s a wide range of modern engines you can swap into your F-100. Restomod allows for a vintage vehicle to have modern comforts. Including the modern comforts of a more powerful engine.

LS F-100 Swaps

It’s hard to think of an engine swap that’s more supported than an LS engine swap. There are entire forums dedicated to LS swapping everything from a lawnmower to a modern drag car. This is partially because the LS was designed to be swap-friendly.

The LS engine is notable for being a modern pushrod engine. While most manufacturers went to the modular engine style, the LS was introduced in ‘95 with an overhead valve configuration. This means that it’s compact while still using modern design improvements.

LS engines have been used in everything from Silverados to Corvettes. That means you’ll have an easy time finding one in a junkyard if you want. The particularly high-end LS engines tend to be a little more challenging to find.

You can also buy a brand new LS crate engine. These options typically come with more guarantees and often even warranties. Junkyards tend to create their own policies, so you’ll need to check with your local one to see how they compare.

Coyote F-100 Swaps

Unsurprisingly, F-100 Coyote swaps are very popular. That’s because Coyotes have a lot of horsepower, and there are lots of aftermarket parts available.

Because the Coyote is a dual overhead cam (DOHC) engine, it’s one of the largest you could try to squeeze into an F-100. This means it’ll need a lot of help to fit into the engine bay of a standard F-100.

One of the first choices you’ll need to make with an F-100 Coyote swap is whether you want to go with an F-150 or Mustang-sourced Coyote. Ford makes engines for both, and there are significant differences between the two.

The F-150 Coyote is a little bit torquier but has less high-revving power. It also has a larger intake manifold, which some swappers have noted is challenging to fit into the F-100.

Mustang Coyotes tend to be more powerful and a little bit smaller. This is reflected in the Mustang Coyotes’ price, which is almost always much more expensive. They’re also much harder to find used.

Though the Coyote is an awesome option, it’s also an expensive one that requires a lot of work.

Hemi F-100 Swaps

Hemis are popular engines. They come in a wide range of displacements, and have been around since the ‘50s. Modern Hemis tend to be larger, almost always greater than 5.0L. They also tend to be powerful.

These powerful V8s have been used in a variety of applications. You can find them in pickups and sports cars alike. It’s especially easy to find older used Hemis.

Unfortunately, shoving a Dodge engine into a Ford pickup isn’t going to be the easiest engine swap. And because it’s not as popular as other options, it’s much harder to find the parts you’ll need to make these two talk to each other.

Also, because most of the modern Hemis are so large, installing one is even more challenging than installing a Coyote.

The general consensus on this swap is that if you’ve already got a spare Hemi laying around, why not? It’s a great engine, and having a Hemi-swapped F-100 would be very cool. Depending on which Hemi you pick though, you may end up needing to contact a custom fabricator to get it completed.

Diesel F-100 Conversions

Many F-100 owners are especially interested in converting their truck to a diesel engine. While diesel conversions aren’t for the faint of heart, they do offer more torque than most gas engines. There are some other benefits to diesel engines, but on a small passenger truck, they’re negligible differences. You might get slightly better gas mileage, but only by a mile or two a gallon. Not enough to justify the cost.

The main reason people choose to swap a diesel engine into their F-100 comes down to loving diesel.

The differences between diesel and gas-powered engines mean you’ll end up replacing a lot of parts. And these parts aren’t usually easy to come by or even available without fabrication.

Most successful diesel swaps start with a vehicle that was available in diesel and gas. The F-100 never was. Intermittently, the Ford Super Duty trucks were available with an IDI Harvester engine.

If you’re determined to do a diesel swap, many F-100 owners have had success with the 5.9L 12-valve Cummins crate engine. This seems to be a reasonable size for most F-100s, and provides large power gains.

What Else Do You Need For a Swap?

Engine swaps involve swapping a whole lot more than an engine. Depending on which engine you select, you’re signing on for many upgrades.

Transmission

One of the most obvious changes that will need to be made is to the transmission. If you’re upgrading to a more powerful engine, it’s likely that it will require a more powerful transmission. When upgrading your transmission, you’ll also need a new clutch/flywheel or flexplate.

Driveshaft

Driveshafts usually need to be resized or replaced when swapping out an engine and transmission. For many, this provides the perfect excuse to upgrade their driveshaft, while others opt to carefully shave theirs down to the new size.

Suspension

More powerful engines frequently mean heavier engines. And heavier engines mean looking at new suspension components. For the most part though, modern suspensions are going to be way better than the options your F-100 had stock anyway. This is a great time to improve your ride and handling in addition to your horsepower.

Brakes

Okay. Technically, you don’t need to upgrade your brakes for an engine swap. But if you’re going from 100 to 400 horsepower, it’s probably a good idea. Being able to stop is as important as being able to go.

Exhaust/Intake

Exhaust and intake manifolds are sized for the engine that you have now. While many new crate engines come with these two parts, a lot don’t. You’ll need to make sure that you have a properly mated intake and exhaust manifold.

This is also a great time to trade your exhaust manifold in for long tube or shorty headers. Upgrading to headers will improve your engine’s power and sound in addition to facilitating a swap.

ECU

Modern engines are going to immediately be looking for a “connection” in your F-100. The engine control unit (ECU) reads information from sensors to make adjustments to the engine. You’ll need to purchase an ECU and attach the sensors to have the engine function properly.

Your Engine-Swapped F-100

Engine swaps can make sense for a wide range of F-100 owners. As classic pickups age, it becomes necessary to replace their engines. Restomod engine selections can offer the best of both worlds, but period-appropriate engines make for an easier swap. No matter which direction you choose, you’ll have an F-100 that runs as well, or better, than the day it was made.

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