Ford Coyote Engines. Jim Smart
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The 5.0L Ti-VCT Coyote block is a durable machined casting right out of the box. It can easily withstand outrageous amounts of power courting the 600- to 800-hp mark. The 5.0L Ti-VCT block shares the same bore spacing (3.937 inches or 100 mm), deck height (8.937 inches), bellhousing bolt pattern, and external dimensions as the 4.6L SOHC and DOHC engines. Bore size was increased to 3.629 inches (92.2 mm) along with an increased stroke of 3.649 inches (92.8 mm), which was still a “square” engine design with identical bore and stroke. Where the Ti-VCT 5.0L block differs is in an entirely new design with heavier webbing and other internal improvements intended to support greater power output from modest displacement.
When the Coyote was introduced for 2011, Ford said, “This aluminum block was developed for optimized windage and oil drainback under lateral conditions and high-RPM use, such as a track-day outing,” meaning this was an engine designed specifically for performance. Ford added, “Increased main bearing bulkhead widths and nodular iron cross-bolted main bearing caps with upsized bolts were also employed to accommodate the significant performance increase.”
The Ti-VCT engine employs a rugged aluminum block with paper-thin iron cylinder liners. Because the Coyote’s iron cylinder liners are quite thin, this block must be sleeved with thicker cylinder liners for all-out racing in the 800- to 1,500-hp range. Modular Motorsports, as one example, offers racers the Pro Mod Coyote block with extra-thick ductile iron cylinder liners that stay put, ensuring block integrity. You can build one of these thick-cylinder bore blocks for the street if you’re an avid weekend racer. Thick cylinder liners are a good life insurance policy for a block already able to take extreme punishment. Cylinders can be bored as high as 3.700 inches to achieve 5.2L.
The basic 5.0L Ti-VCT block is the most rugged Modular-based casting to date, but it has nothing in common with the 4.6L Modular except bore spacing and deck height. This block can withstand 800 to 1,000 hp, although it is suggested that you opt for the Pro Mod or Holbrook block with thicker cylinder liners if you plan on pushing power beyond 800 hp.
Holbrook Racing Engines offers its own thick-cylinder-liner Coyote block as well. Holbrook can take your block or an existing block from stock and set you up with an improved thick cylinder block, which can also be bored to 3.700 inches.
Rugged block architecture is what holds this engine together. Main bearing webs are thicker and heavier, allowing for performance extremes from enthusiasts and Ford product planners. This means the basic Coyote block can stand up to naturally aspirated performance demands, supercharging, nitrous, direct injection, and more. It can be said with confidence that this block will withstand more than 1,500 hp when sleeved with the thicker ductile iron cylinder liners mentioned earlier.
Performance enthusiasts like the Coyote block with its extensive network of ribs and beefcake support, which means strength and durability. These left-side (driver) block casting ribs and gussets provide unprecedented strength across block decks and pan rails. Cross-bolted main caps with interference fit provide the security of Fort Knox. One weakness has been among 4- and 8-cylinder bores, which have experienced cooling problems and blown cylinder walls. Improved coolant flow at the back of the block and heads can solve this problem.
The right side (passenger) yields the same story of crossed, vertical, and horizontal ribs providing extraordinary strength. What this means for you is a bulletproof block for street and weekend strip activity.
It used to be that rear main seals were integral with the five-main-bearing cap; not anymore. The rear main seal is fitted into a bolt-on cast-aluminum aft block cover, which is separate from the five-main-bearing cap, which makes rear main seal replacement easier and ensures a more leak-proof seal.
Skirted blocks, an old-school design approach that went away with the 90-degree Fairlane V-8 (221/260/289/302/351W) and 385-series big-blocks (429/460) designed in the 1960s, is back because it provides the greatest strength around a high-revving bottom end. The 5.0L Ti-VCT is a “square” engine (identical bore and stroke) that likes to rev. This engine makes its greatest power at high RPM. The downside to this design is limited potential for growth. You can’t make this engine any larger than 5.0L unless you go with thicker cylinder liners. And with that, the most you can go is 5.2L.
With this new block come advances in crankcase ventilation known as “bay-to-bay” breathing. Ford engineers located venting in the main webs designed to allow the freedom of air scavenging without robbing power. The result is a more positive ring seal, which helps efficiency and power. Gone is the Modular’s coolant tube down the middle of the valley. Instead, coolant is routed through the front of the block, leaving plenty of room for exotic induction systems and superchargers.
In the spirit of classic Ford 406 and 427 FE-Series big-blocks, the Coyote has cross-bolted main caps. The Modular 4.6L/5.4L engines had jackscrews (Romeo) or dowel pins (Windsor) to shim up main caps. The Ti-VCT Coyote does the Modular engine one better with perfect-fit main caps machined exactly to the proper size so that jackscrews and dowels are unnecessary.
These piston-cooling oil jets provide good heat transfer to the oil, which carries excessive heat away, especially in boosted applications. Some confusion surrounds them because the 2011–2013 Coyote blocks had them and then Ford dropped them. In the course of 2015–2016 production, piston-cooling jets returned. Expect to see some blocks with this provision and some without.
Here’s a Coyote block without the piston-cooling jet provision. Unless you’re opting for supercharging, turbocharging, or nitrous, you probably don’t need them. Forged and coated pistons probably don’t need them either. The logic is better to have and not need them than need them and not have them.
The Coyote’s bottom end from another angle demonstrates how rugged this engine is. Whether you are towing, hauling, or racing, the Coyote is up to the task. Properly torqued to Ford’s critical specifications, this is a virtually bulletproof bottom end that can take anywhere from 600 to 1,000 hp. With thick-wall cylinder liners and a studded ARP fastener bottom end, your Coyote will stay together beyond 1,000 hp.
A close-up look illustrates the Coyote’s paper-thin iron cylinder walls. Believe it or not, these cylinder sleeves can withstand 600 to 800 hp. Although some have gone to 1,000 hp without consequence, it is strongly suggested that you