Ford Coyote Engines. Jim Smart
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You’ve been told about the Pro Mod block in this chapter. Modular Motorsports offers racers the Coyote Pro Mod block, which is fitted with extra thick ductile iron cylinder liners that are siamesed as shown for unprecedented strength. Modular Motorsports says that the Pro Mod block can take more than 1,500 hp. These sleeves can be bored to 3.700 inches to get 5.2L displacement.
Head on, it’s challenging to differentiate the Coyote from a 4.6L block. However, closer inspection demonstrates revised cooling and oil passages. You no longer have to sweat out the valley cooling tube as you did with the 4.6L because cooling passages are now in the block.
Bore spacing is the same as the 4.6L and 5.4L blocks. However, bore size is larger via iron sleeves pressed into the aluminum block. In addition, the 5.0L embraces vastly improved cooling to handle higher compression and extreme performance duty. Note the generous cooling passages. This is a block engineered for the toughest racing conditions because Team Coyote didn’t want to have to come back years later and do it again.
One of the quickest ways to identify the Coyote block is by this webbed crosshatch valley with a slight rise in the middle. None of the 4.6L block castings look this way. The nice thing about the Coyote block is plenty of valley space for superchargers and exotic induction systems. Gone is the 4.6L’s cooling tube. The Coyote block routes coolant through the block instead of the valley.
The Modular V-8’s cooling tube down the middle of the valley is not present on the Coyote. Instead, coolant is routed through the front of the block, leaving plenty of room for exotic induction systems and superchargers. Any way you view the Coyote block, it is a vast improvement over the Modular.
Because this is a 7,000-rpm engine, the Coyote is fitted with an induction-hardened, fully counter-weighted crankshaft that’s virtually indestructible, featuring an eight-hole flange. Team Coyote elected to stay with the 4.6L engine’s main and rod journal dimensions because they have been a proven success in nearly two decades of production in every application imaginable. In addition, aluminum bearings were borrowed directly from the 4.6L engine instead of tri-metal bearings because they have worked successfully.
The Ti-VCT’s forged steel crankshaft has the same dimensions as the 4.6L with 2.652-inch main journals and 2.086-inch rod journals along with a complete counterweight package. Ford stayed with this package because it is race proven. And, the Coyote’s crank has withstood extremes of dyno testing without failure.
The Coyote’s forged steel crank has an eight-bolt flange and is an extreme-duty part. The 4.6L Romeo engines were six- and eight-bolt flanges depending upon application. All Windsor/Essex engines have been essentially truck engines and eight-bolt. Ford is extremely committed to eight-bolt in the interest of safety and durability.
Like the Modular engines, the Coyote has a powdered-metal connecting rod measuring 5.933 inches center to center and has proven quite durable in applications up to 500 hp. In fact, we’ve seen the stock rod pushed to 600 hp without consequence. However, would you want to take that chance? Anything beyond 600 hp calls for the brute Manley H-beam rod if your goal is true durability.
Ford learned a lot about durability with the Modular engines. It found you don’t always need a forged piston; a well-thought-out hypereutectic piston works just as well. Hypereutectic offers strength without the challenges of forged. Forged pistons yield greater expansion properties and can be noisy when cold.
The Coyote engine shares the same connecting rod dimensions with the 4.6L engine at 5.933 inches center to center; yet it is not the same rod. It is a stronger rod with 12-point bolt heads. Rod ratio is 1.62:1 for excellent dwell time at each end of the bore. The Coyote’s 5.933-inch cracked rod is a sintered metal I-beam piece engineered for extreme street and weekend race duty. However, it is not a rod that stands up to the severe punishment of supercharging and nitrous. If you’re planning a supercharger or nitrous induction, Manley H-beam rods are mandatory over the stock 5.933-inch rod. The stock rod takes a lot of punishment. However, you’re pushing your luck if you use anything less than a heavy-duty forged-steel I-beam or H-beam rod if you plan to push it above 600 hp.
The Coyote piston, shown from another angle, demonstrates how different this slug is from those in the 4.6L/5.4L Modular. It is a lighter piston sporting a protective coating, enabling it to survive higher-combustion temperatures.
The Coyote is fitted with lightweight hypereutectic pistons with coated skirts for reduced friction and wear. Ford engineers weighed the benefits of forged versus hypereutectic and hypereutectic won for its weight and expansion properties. Forged pistons are noisy when they are cold due to excessive piston to cylinder wall clearances, which generate plenty of complaints with 4.6L and 5.4L engines. Hypereutectic pistons run quieter because you can run tighter tolerances without noise when they are cold. The Coyote piston tolerates the extremes of street and weekend race duty and offers durability. However, if you intend to supercharge or use nitrous you’re better off with a forged and coated piston for best results.
Another reason Ford opted for a hypereutectic piston is the oil cooling jets that keep the pistons cooler, which improves piston life. This approach also allows for faster warm up because oil is in direct contact with one of the hottest parts of the engine right from the start. Ford engineers proved that the crankshaft runs roughly 25 degrees F cooler with the oil jets, which enables this engine to operate on 87-octane fuel and survive (although 91-octane is optimum).
Coyote four-valve cylinder heads are left and right specific as well as being a fresh design from Ford. These DOHC heads are downsized for a more compact Modular design with less restriction and improved flow. Cam journal support is more “Windsor” in nature: void of girdles with the simplicity of standalone cam journals. This is a CNC-ported 2011–2014 cylinder head. The stock ports are roughcast.
Most important to remember is clearance issues. Heavy-duty I-beam and H-beam connecting rods don’t always clear the tight confines of the Coyote block. You must first do a mock-up and make sure everything clears by at least .060 to .100 inch throughout 360 degrees of crank rotation with all rods and pistons (without rings) installed. Pay close attention to piston skirt to crank counterweight clearances, which can become very tight and prohibit the Coyote from accepting any more than a 3.649-inch (92.5-mm) stroke. Another area of consideration should be connecting rod interference issues with the piston cooling