Ford’s 5.0L Ti-VCT Coyote employs a revolutionary new cylinder head design that makes the latest member of the Modular engine less bulky while providing extraordinary breathing. The Coyote’s intake ports utilize true drive-through service because they outflow even some of the most legendary race heads in history, including the Yates D3 casting for the small-block Ford. Perhaps this is an unfair comparison when you consider a two-valve versus a four-valve. But airflow is airflow and power is power. What counts is what you get at the crank and rear wheels.
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Known stock Coyote intake port head flow numbers are 289.4-cfm intake and 201.4-cfm exhaust at .500 inch, which is remarkable, but there’s more. Because the Coyote’s top end was designed more as a package than just cylinder heads, cam, and induction, it produces impressive airflow numbers rarely seen from a factory Ford engine. Call it the team approach to induction, cams, and heads. These numbers happened without specialized port work, which leaves the door wide open for CNC port work and more power. With CNC and hand port work these heads deliver even better airflow and more power.
Ford’s Coyote design team understood at the outset it would have to burn a lot of midnight oil to come up with a cylinder head that could do everything. Ford engineers looked first to basic hotrodding tricks to achieve their goals and then went to work conceiving a better cylinder head. Although the Coyote cylinder head appears to be a derivative of the Shelby GT500 head, it isn’t. If you study this head closely it is a completely different casting. A lot was learned from the GT500 head, yet none of it was carried directly over to the Coyote, according to Ford.
Ford engineers also took what they learned from the 3.5L and 3.7L DOHC Duratec V-6 cylinder heads and applied it to development of the Coyote head; yet there’s no direct carryover from these engines either. However, the 3.5L/3.7L four-valve combustion chamber technique was applied to the Coyote to some degree in terms of shape and valve placement. Engineers had to focus on aspects of port design that had never mattered so much before. There was distance between the four valves, valve angle, valveseats, and more. Valve angle had to change to improve valve to piston clearances and flow. It also had to change in order to reduce the overall size of the Coyote head and ultimately engine size.
Everything in the Coyote’s cylinder heads had to be downsized to achieve a more petite cylinder head casting size. This meant smaller lash adjusters, springs, and rocker arms. When you compare the Coyote’s valves and valvetrain to the 4.6L and 5.4L Modular’s, there’s an obvious difference in size. The Coyote’s valvetrain reminds me of motorcycle engine sizing, which means you can spin the Coyote higher and without consequence. Cams had to be brought 20 mm closer together to shrink the package. Romeo-style camshaft journal girdles were abandoned for Windsor-style camshaft journal towers. Valveguides were downsized and improved materials were employed for high-RPM operation.
Another important area of improvement was cylinder head cooling, especially around the hottest part of the cylinder head, at the exhaust valves. Ford calls the improved method “cross-flow cooling”; it eliminated the Modular’s cooling tube in the valley. Coolant flows up through cylinder heads at the exhaust valves toward the front of this engine. Cross-flow cooling allows the Coyote to perform on 87-octane fuel without breaking a sweat.
Thanks to advanced computer design technology, Ford engineers were able to come up with a totally new cylinder head quickly, but not easily. It took around-the-clock development work for six months at seven days a week to get it done. The Coyote head’s development and execution was a remarkable turn of events for Ford because it had never been done.
When development began on the base Coyote head, Ford engineers were presented with another challenge: the 2012–2013 BOSS 302 cylinder head, which was also known as the “Roadrunner” project inside Ford. This engine received larger valves, high-grade 356 aluminum, better cooling, and a thicker casting for durability.
Ford was able to develop the BOSS 302 head thanks to being given a proper budget. What resulted were the left-hand M-6050-M50BR (driver) and right-hand M-6049-M50BR (passenger) heads. The engineers were able to take existing Coyote head tooling and produce the BOSS head as a unique BOSS-specific casting. Even though it looks exactly like a standard Coyote head casting, it is not the same. The BOSS head is cast of 356 aluminum alloy with a smattering of copper for both strength and good heat transfer. It sports plenty of thick aluminum stock where it counts, at the deck and around the valves.
When a casting emerged from the Windsor foundry, CNC machines went to work to massage the unique BOSS casting which, to the naked eye, isn’t much different from the standard Coyote head. In terms of power and function, how ever, it is surely a different head. With the BOSS head you not only get improved function but also strength in a better-alloy cocktail. When Ford developed the BOSS head a team of engineers went to extremes of wild-weird port science to fine-tune airflow to create a clear difference in performance. Ford engineers worked day and night on intake and exhaust port shape with grueling dyno tests to determine how much they had gained. It didn’t happen all at once. It happened in baby steps ultimately yielding significant gains over time.
As engineers massaged intake ports they found that conventional port logic didn’t always net them improvement. Improvement came with minute changes in port shape. Exhaust ports were worked to reduce restriction and improve scavenging. Ford engineers achieved improved flow by also lowering the port floor.
GT350 Coyote Cylinder Head
Ford Performance is introducing the Shelby GT350 5.2L cylinder head at press time, along with the corresponding induction and cylinder block, making it possible to build a 5.2L Coyote with the cross-plane crank (more cubes for your Coyote project and the added benefit of these GT350 heads). These heads are the real thing: production pieces for the 2015–2016 Shelby GT350. Here’s what you get:
- Production cylinder head for the 5.2L GT350
- Fully CNC-ported intake ports, exhaust ports, and combustion chamber
- Larger port sizing than the 2015 5.0L Coyote CMCV cylinder heads
- 38.3-mm intake valve and 32.5-mm exhaust valve; 2015 5.0L Coyote valve sizes are 37.3-mm intake, 31.8-mm exhaust
- New valvetrain geometry allows for greater valve lift
- Lightweight hollow-stem intake valves and sodium-filled exhaust valves
- Heads do not include camshafts, rocker arms, and lash adjusters
- Requires unique camshaft due to valvetrain geometry (M-6550-M52)
- Also requires 5.2L rocker arms and lash adjusters (M-6564-M52)
The GT350 head really is a different cylinder head for the Coyote with very little that interchanges due to this head’s unique valvetrain geometry. Budget permitting, you can build a complete Ford Performance 5.2L Coyote to create a completely compatible mill. Ford Performance expects to have a complete 5.2L Coyote crate available by fall of 2016 that you can order with the cross-plane crank. Sorry, flat-plane cranks are not expected from Ford Performance anytime soon. They are a GT350 exclusive; you have to buy a GT350 to get one. Complete 5.2L Voodoo flat-plane engines are not expected either from Ford Performance.
The GT350 cylinder head is a ready-to-race piece right out of the box with its larger valves, generous ports, and revised valvetrain dimensions. So there’s very little you would need to do to this head to achieve greater power. Real power comes from engine tuning once you have the 5.2L together
Improving the Coyote Head
How do you improve on such a perfect factory cylinder head? No one I have spoken with in the automotive aftermarket is planning a high-performance cylinder head for the 5.0L/5.2L Ti-VCT Coyote engine at press time because the factory castings are exceptional pieces to begin with. The best Coyote cylinder head in the marketplace is the factory casting with port work to improve flow numbers.
Regardless of what cylinder head you have planned for your Coyote project, the basics remain the same. Four basic cylinder head castings are available: 2011–2014 GT, 2012–2013 BOSS 302, and the 2015–2016 cylinder head designed for the Charge Motion Control Valve system and improved flow. The new Shelby GT350 5.2L head can also be included.
If you’re going to run the 2015–2016 cylinder head on your 2011–2014 block, use the 2015–2016 cylinder head gasket with the larger VCT oil feed hole in front. If you’re going to run the more aggressive 2015–2016 camshafts on 2011–2014 cylinder heads, you must use the 2015–2016 timing chains, sprockets, and cam phasers. You cannot interchange 2011–2014 and 2015–2016 timing components. Variable cam timing (VCT) phaser bolts are new for 2015–2016 and must be matched to the 2015–2016 VCT solenoids. If you opt for 2015–2016 cylinder heads, be prepared to go the entire way with the complete timing chain and phaser package.
While I’m on the subject of cylinder head compatibility, also keep in mind that the 2015–2016 induction system is also different from 2011 to 2014 with ribbing that interferes with the 2011–2014 cylinder head’s extended intake port flange. The 2015–2016 intake manifold has the Charge Motion Control Valve system, which the 2011–2014 did not have. Charge Motion changes intake manifold runner length via flapper valves in the intake manifold. Greater runner length gives you better low-end torque. Shorter runners make horsepower at high RPM.
So how do you improve an already great factory cylinder head? You can improve the Coyote head with precision CNC port work. Oh sure, you can spend a lot of time hand porting this head if you have a lot of time on your hands. However, you are money and time ahead buying the Ford Performance Racing Parts CNC-ported head or sending your heads to Total Engine Airflow for CNC port work. Total Engine Airflow CNC machines the intake and exhaust ports along with the combustion chambers. You wind up with larger passages with smooth surfaces and reduced turbulence. The result, regardless of how you look at it, is improved flow.
Ford Performance is no longer producing the BOSS 302 cylinder head. However, these heads are still available from sources like Summit Racing Equipment, eBay, craigslist, and a host of others. Remaining inventories of new BOSS heads as well as used show up at swap meets and parts houses. Because the Coyote V-8 in all its forms has been in production a short time, it’s going to take time for used castings to become available. In the meantime, search for new castings for your Coyote project.
TEA CNC-Ported Coyote Heads
Although there are four basic factory cylinder head castings, the aftermarket offers different CNC porting styles you should be familiar with. Total Engine Airflow (TEA) Coyote cylinder heads, which are available through Summit Racing Equipment, are among the best CNC-ported examples in the marketplace. You need to send TEA your cylinder head cores to get started. Here’s what you can expect:
TEA valve jobs optimize airflow to deliver power and durability. They are also blueprint, meaning all seat depths are equal from valve to valve and head to head. There are no variations.
All TEA head ports and chambers are hand blended in critical areas, and then flow tested to ensure they perform as designed. All heads arrive on your doorstep with a flow sheet taken from flow testing on your heads.
Every set of heads is ready to install directly out of the box. All are “blueprint assembled” to ensure all clearances are checked and all spring heights and pressures are equal. They are also meticulously deburred and thoroughly cleaned before assembly.
Many options can be performed on your Coyote cylinder heads. For example, chamber volume can be milled from any TEA cylinder heads to the customer’s requested chamber volume; in some cases they can remove additional material to make the chambers larger if needed. TEA also stocks parts from all the leading valvetrain manufacturers and can supply countless variations of valvesprings, retainers, and valve materials.
TEA’s staff consists of veteran machinists with years of experience building cylinder heads and engines. They understand what lives and what doesn’t.
When your Coyote heads arrive at TEA, here’s what happens:
- Disassemble and clean
- Fully CNC port intake and exhaust runners
- Competition multi-angle valve job
- Precision grind all 32 valves with backcut on intake valve
- Hand blend valve job into porting
- Flow test with sheet included
- Flat mill
- Custom assembly ensuring all tip heights are at stock height
- Trickflow/Pac racing 85-pound valvesprings
- OE valvestem seals
JPC Racing Coyote CNC-Ported Heads
JPC (Justin’s Performance Center) Racing, located between Washington, D.C., and Baltimore, Maryland, delivers a great CNC-ported Coyote Stage 1 head for those of you looking for nice power gains from your naturally aspirated or forced-air Coyote. Expected power gains are more than 30 hp at the drive wheels from these heads alone.
These CNC-ported heads are actually a joint venture between JPC Racing and Rich Groh Racing (RGR) Engines. On its website JPC says, “The Stage 1 CNC-ported heads increase flow 9 to 14 percent (depends on lift) and utilize OEM valves, valvesprings, and retainers. A five-angle valve job is standard with all Stage 1 CNC-ported heads. JPC and RGR completely disassemble the heads, including the valveguides, for maximum porting during the CNC process.” JPC adds that turnaround time is approximately one week because they keep CNC castings in stock. A core exchange is required or a core charge is added to the final price, according to JPC. The JPC Racing Stage 2 and Stage 3 CNC-ported heads have aftermarket oversized valves and upgraded valvesprings.
Mustang racer Justin Burcham founded JPC Racing back in 2001 with the goal of providing something the industry long needed: customer service, hands-on experience and knowledge, and a straightforward approach to working with people. Justin and his experienced staff bring many years of high-performance expertise to the table, along with several NMRA national championships.
Slawko Racing Heads
Slawko Racing Heads is another source for CNC-ported Coyote cylinder heads that contributes a strong racing background and a wealth of experience.
Slawko Racing Heads says these are the same CNC-ported Coyote heads used by Justin Cyrnek in his 2013 Mustang GT racecar. An Evolution Performance and L&M Engines– built GEN 1 5.0L Coyote engine powers Cyrnek’s Mustang. Justin’s best times in this Mustang have been as fast as 7.92 at 173.56 mph in the quarter-mile.
Written by Jim Smart and Posted with Permission of CarTechBooks