When Team Coyote was finished with cylinder head casting development, it had to go back and look at cam profile and the very size and weight of valvetrain components. Ford had to improve mechanical advantage between the camshaft and valvesprings by reducing load. Reduced load came from larger cam lobes, which was a nuance that began with the 4.6L SOHC engine a quarter-century ago.
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A lot of research and development went into these heads to get them where Ford engineers wanted them in terms of size. Consider high-revving motorcycle engines: This is what Ford was faced with in developing the Coyote. Coyote heads and parts had to get smaller, as did valvetrain components. Rocker arms had to be smaller to improve both efficiency and performance. Less reciprocating weight on top meant freedom of speed at higher-RPM ranges.
Put the 4.6L DOHC and 5.0L Ti-VCT DOHC rocker arms side by side and you see the obvious difference in size. The Coyote’s rocker arms are smaller. The 5.0L Coyote engine does it with less mass and weight. Furthermore, it enabled Ford to reduce cylinder head size and width, reducing overall engine width. The result has been a higher-revving engine with less mass from shoulder to shoulder. In fact, the Coyote is small enough to fit into a 1979–1993 Fox Mustang or the 1994–2004 SN-95 thanks to this overall reduction in size.
The Coyote’s valvetrain system is the most complex ever installed in a Mustang or F-Series truck and it is designed to optimize all driving conditions. Remember that “Ti-VCT” stands for “Twin Independent Variable Cam Timing.” This means intake and exhaust cams work independent of each other based on driving demands. The system advances cam timing on each side as necessary based on conditions and throttle position. Each camshaft is indexed, or phased, around its centerline by oil pressure. Oil pressure is metered electronically via solenoids and phasers to control cam indexing as required.
The Coyote’s overhead cam Variable Cam Timing (VCT) system is the most advanced in Ford history. It advances cam timing as required by the PCM. Oil pressure, which is applied to the cam phasers by electronic solenoids at each phaser, advances cam timing by turning the cam on its axis. For 2011–2014, this system isn’t as advanced as it is for 2015–2016 where cam timing is more finite in scope.
These are the cam phasers, which advance cam timing based on PCM input via solenoids at each phaser. This is the right-hand-side (passenger) cylinder bank.
Here’s the left-hand (driver) cylinder head with the same cam phasers and solenoids. The timing Chain drives the exhaust cam. The exhaust cam sprocket (right) drives the intake cam sprocket (left). Oil pressurized chain tensioners maintain chain tension at the cam phasers and secondary timing chains.
In back of each cylinder head are trigger wheels at the end of each camshaft (top arrows). In the cylinder head is a Hall Effect sensor for each cam (bottom arrows). The sensors are missing here; arrows indicate the sensor bung holes in the head.
The Coyote V-8 employs a similar camshaft drive system to the 4.6L and 5.4L DOHC engines with a timing chain for each bank, which drives the exhaust cam. A smaller secondary chain between cams drives the intake cam.
Ti-VCT enables the Coyote to deliver a wide power band across the RPM while giving you the bonus of high-end horsepower, which was never easy to achieve before with conventional methods. Cam torque actuation, which uses valvespring energy to retard timing more quickly depending on engine RPM and driving demands, is the feature that sets the Coyote’s Ti-VCT apart from the rest of the Ford line. Instead of a complex electronically controlled shuttle valve and oiling system routing, the Coyote’s Ti-VCT is a simple on/off solenoid to advance valve timing; cam torque from valvespring pressure does the retarding. Oil pressure advances cam timing and cam torque from spring pressure retards timing.
Ti-VCT can advance/retard valve timing by as much as 50 degrees and do it in .2 second. This approach offers you modest valve timing on the way to work and more aggressive valve timing when it’s time to get it on. For the environmentally conscious, the Coyote doesn’t need EGR (exhaust gas recirculation) because valve overlap is increased in certain types of driving, especially deceleration, which reduces hydrocarbon emissions.
What makes the Coyote different is the VCT sprockets/phasers that index the cams based on PCM input and oil pressure modulation at the phasers. As with the 4.6L and 5.4L engines there are chain guides and tensioners that keep the chains tight. Tensioners are oil pressure modulated.
Here’s a close-up look at the left (driver) oil pressure–actuated chain tensioner. These are no-adjust components. They apply pressure to the chain guide to maintain chain tension.
This is the right-hand (passenger) chain tensioner. It is, in principle, virtually the same as the 4.6L and 5.4L chain guide system.
Both timing chains meet at the crank sprocket as shown. The left-bank (driver) chain is installed first, then the right (passenger). Timing marks on the links and gears allow timing adjustment during chain installation.
In order to do the complex work of Ti-VCT and other critical functions, Ford’s EEC (Electronic Engine Control) was asked to do more than it ever had in its history. It became known as the Copperhead system, a new multi-channel system designed to control every aspect of engine and driveline including Ti-VCT. Instead of a simple on/off system of cam modulation, Ti-VCT advances valve timing on each cam for fine-tuned operation. Electronic control monitors and controls oil pressure to the cam phasers. It isn’t just advance/retard; it actually modulates both elements in degrees based on driving demands.
Ti-VCT isn’t something you need to worry about maintaining or tuning. It is a “life of the engine” system. If the cam phasers fail, they’re easily replaced by removing the cam and timing covers, aligning timing marks, and replacing the phasers. What makes the Coyote’s phasers different from the 3V Modular’s is cam position sensor location, which is at the opposite end of the cam on the Coyote.
This chain tensioner is properly prepared for installation. The installation pin keeps the tensioner piston compressed. After you have the chains, guides, and tensioners installed, the pin is pulled, which applies chain tension.
The back side of the phasers shows the modulation valve in the center.
On top is a look at the complete valvetrain system. Before you are the intake and exhaust cams, which ride in pressurized journals on an oil wedge. Beneath the cams are finger-style roller rocker arms, which are positioned on top of lash adjusters.
These lightweight petite roller rocker arms are a no-adjust affair. Pressurized hydraulic lash adjusters or followers maintain valve lash. Moreover, these rockers can withstand the severe punishment of a radical cam and 1,500 to 2,000 hp.
Cam sprocket phasers advance cam timing as solenoids actuate a button in the middle of the phaser, which is valved to modulate cam movement. These phasers are interchangeable from side to side. These are 2011–2014 phasers. The 2015–2016 phasers are different in both appearance and function. The “R” and “L” timing marks are left- (driver) and right-bank (passenger) installation.
These PCM-triggered solenoids meter oil pressure to the cam phasers to advance cam timing (VCT). There is a difference between 2011–2014 and 2015–2016 VCT systems. You must have complete compatibility, all 2011–2014 or all 2015–2016.
Improving the Coyote Valvetrain System
What can you do to improve the Coyote’s valvetrain system? The Coyote’s rocker arms are petite, stamped-steel, heavy-duty rollers that can stand up to the punishing abuse of the most aggressive cam profiles. At present, the aftermarket isn’t producing a roller rocker for the Coyote. As cam profile aggressiveness increases, however, valvespring pressure must increase accordingly. The key to durability and performance is matched components from the aftermarket. Ideally, you buy camshafts and springs as a set. Your cam manufacturer can advise you on which spring, retainers, and keeper to choose.
Unless you are going racing or are on a steady diet of street/track it makes little sense to lock in cam timing. If you opt for a hotter cam you’re going to need to install cam phaser limiters or adjustable sprockets for more controlled valve timing.
Here are the Coyote’s twin cams: one intake and one exhaust. At one end of each cam are the triggers/reluctors. At the other end is the cam phaser (not pictured here) journal.
A close-up view of the cam phaser end with its oil passages for cam phaser function. This end goes toward the front of the engine. The “D”-shaped indent is also a timing mark for proper cam indexing during installation.
This is the trigger/reluctor end with its sensor nodes. As these nodes pass the sensor they trigger a pulse signal for the PCM/ECU, which controls engine function in real time.
All Modular engines, including the 4.6L, 5.4L, 6.2L, and the new 5.0L, are factory fitted with composite camshafts, which are a hollow tube with individual lobes that are positioned onto the shaft as shown. Note the deep peen marks in each lobe.
You may opt for a more aggressive cam profile from Comp Camsor Ford Performance Parts and wind up with a user-friendly valve action program that infuses more power into your Coyote. Cam swaps are easy on the Coyote. Even valvespring replacement is straightforward if you have the right tools. You can do a cam and/or valvespring swap without pulling the heads. And if you have to pull heads for something like CNC port work, cylinder head removal and replacement is straightforward whether you have a Mustang or F-Series truck.
When you are performing topend work on your Ti-VCT Coyote, you’re going to need the head swap kit (M-6067-M50) from Ford Performance Parts. Cometic and Fel-Pro cylinder head gaskets are another viable option available from your local auto parts store or Summit Racing Equipment. Always replace cylinder head and cam journal bolts, which are torque-to-yield and can only be used once. Once torque-to-yield bolts have stretched one time they’re basically a throwaway and should not be used again.
Camming Up
Ford did a good job of camming the Ti-VCT Coyote from the factory, including the BOSS 302 sticks. However, Comp Cams has undertaken a lot of research and development time with the Coyote and come up with aggressive cam profiles engineered to meet some of the toughest street and strip requirements.
Comp Cams claims that its billet hydraulic roller cams for the Coyote unlock a lot of hidden power, which I have proven via dyno testing at JGM Performance Engineering for this book. Cams are available for naturally aspirated and blown applications with three cam profiles each from Comp. Each is dynamic balanced for smooth operation in the Coyote. Comp Cams says the XFI NSR (191160) cam can produce as much as 417 hp and 382 ft-lbs of torque at the rear wheels with long-tube headers and a JLT induction system, based on in-house testing.
The Coyote’s front timing cover has nothing in common with the 4.6L engine it replaces. It is not interchangeable.
Here’s the backside of the Coyote timing cover with its continuous gaskets, which provide perfect sealing. The key to effective sealing is proper installation: The seals must be firmly seated with solid contact. Lube the seals with a thin film of engine oil and ensure that they are fully seated prior to cover installation.
We have dyno tested a 2011–2014 crate Coyote from Ford Performance at JGM Performance Engineering and experienced in excess of 500 hp at the crank from both the Ford Performance BOSS 302 cams and the Comp Cams 191160 with BOSS 302 and Cobra Jet induction. With the Comp 191160 grind and Cobra Jet induction it came in just shy of 600 hp.
Ford Performance BOSS Cam
The 2012–2013 BOSS 302 camshaft set (M-6550-M50EXT and M-6550-M50BINT) offers more lift and duration for improved performance without having to use cam phaser locks. These cams were used in both the BOSS 302 Coyote and the Cobra Jet. They are good cams for the money with few modifications required.
Chains and Guides
The 5.0L Ti-VCT Coyote has a series of timing chains and guides similar to the 4.6L DOHC engine. Chain tensioners are oil pressure modulated just like the 4.6L/5.4L engines. Chains travel through plastic guides between the crank and camshaft sprockets. The installation and proper timing of these chains and sprockets is simple if you take your time and pay close attention to what you’re doing. It can be said with confidence that the stock Ford chain guides take tremendous amounts of abuse. They are “life-of-the-engine” pieces engineered to last 100,000 to 200,000 miles in normal use.
Although the Coyote’s finger-style roller rocker arm and lash adjuster resemble those on the 4.6L/5.4L Modular family, these rockers are downsized from their Modular cousins and are not interchangeable. At press time the aftermarket hasn’t produced a high-performance roller rocker arm for the 5.0L Coyote. The factory stamped-steel roller rocker can withstand 1,500 to 2,000 hp, which makes it suitable for any Coyote project.
Note: The 2015–up Coyote engines do not require modified cylinder heads or changes to cam phasers. The CR Series cams for 2015–up have revised lobe centers and more lift yet work with stock valvesprings and Ford mid-lock phasers. Two upgrade spring kits are available if you desire greater spring pressures.
If you’re concerned about failure issues, you can step up to hardened crankshaft gears from Modular Motorsports Racing or Ford Performance Parts. Modular Motorsports Racing (MMR) has billet chain guides for your Coyote project if you’re going racing. The MMR pieces can be found in a lot of racing Coyotes, be they drag or road race. For the street only you can get by with original Ford parts, the M-6004-A504 complete chain drive kit, which is available from Ford Performance Racing Parts or Summit Racing Equipment.
Although the Coyote’s finger-style roller rocker arm and lash adjuster resemble those on the 4.6L/5.4L Modular family, these rockers are downsized from their Modular cousins and are not interchangeable. At press time the aftermarket hasn’t produced a high-performance roller rocker arm for the 5.0L Coyote. The factory stamped-steel roller rocker can withstand 1,500 to 2,000 hp, which makes it suitable for any Coyote project.
The Coyote’s timing chain drive system is easy to understand and simple to time. All you have to do is match marked chain links and phaser/ sprocket timing marks. This is a Ford Performance Racing Parts Aluminator Coyote, 9.5:1 compression, for supercharged applications. Note the stock chain guides. Yeah, it’s that good.
The Modular aftermarket offers highperformance billet timing chain guides such as these from Modular Motorsports Racing (MMR). They provide extraordinary durability under extreme conditions.
If you are opting for an aftermarket high-performance camshaft package, some kits call for the installation of cam phaser locks to keep timing consistent and eliminate the risk of valve to piston contact. Comp Cams has an adjustable cam phaser lock system that enables you to lock in cam timing. In addition, you can fine-tune the lock system for your individual requirements. MMR also manufactures an adjustable cam phaser lock kit for the Coyote.
When you’re planning your Coyote project there’s comfort in knowing that this engine has few weak links. Valvetrains are traditionally the weakest element in any engine. Your valvetrain system can benefit from compatible spring pressures and cam profiles. You want the best retainers and keepers money can buy, even if you’re building a stocker. If you’re opting for an aggressive performance cam for your Coyote, buy a complete cam and valvetrain kit.
Ford Performance Racing Parts offers a complete timing system kit, M-6004-A504, for the Coyote, which makes your job as an engine builder easy. Everything you need to finish out a Coyote build is here, including timing chains, phasers/sprockets, chain guides, tensioners, crank sprocket, and all mounting hardware. (Photo Courtesy Ford Performance Parts)
Chain tensioners are available from Ford Performance Racing Parts, M-6266-M50B, if you’re equipped with everything else you need to assemble the timing system package. These tensioners are powered by engine oil pressure (hydraulics) to do the grunt work of timing chain tension and security. (Photo Courtesy Ford Performance Parts)
Heavy-duty timing chain tensioners are available from Modular Motorsports Racing (MMR) for your Coyote build. These are a nice asset for a stock or modified engine build because they offer extreme durability.
If you’re building a 2011–2014 Coyote, you can lock-in cam timing with these MMR cam phaser delete plates. These Ti-VCT phaser deletes eliminate 274 grams on each exhaust cam and 330 grams on each intake cam, which means 1,208 grams or 2.6 lbs of rotational weight lost, plus allowing full adjustability of your Coyote camshafts.
Whenever you step up to a more aggressive camshaft, make sure that you confirm valvespring requirements from the manufacturer. If you’re in doubt, go to a stiffer valvespring for better results at high RPM. Few things are more discouraging than a hot cam and valve float at high RPM. Always follow the cam manufacturer’s instructions to the letter. If you get stumped, call the manufacturer’s tech line. The one thing you do not want is bent valves or more serious engine damage because you didn’t follow instructions.
The nice thing about the Coyote is the easy access to camshafts, valvetrain, and cam phasers. Remove the cam and timing covers and it is all right there for easy access. The key to success is getting the number-1 piston at true top dead center with all of the marked timing chain links at the marks before youstart swapping cams. When you are there, never change either the cam or chain position. If you are performing a cam swap, take note of camshaft position and install new cams at the exact same indexing. If you are not focused, this is an easy mistake to make.
These are Comp Cams’ fully adjustable cam phaser elimination plates, which enable you to lock in cam timing. These plates are easy to access on the Coyote, enabling you to fine-tune cam timing quickly.
When you eliminate the cam timing phasers you no longer need the VCT solenoids, which protrude through the cam covers. Remove solenoids and plug cam cover holes.
If you’re building a Coyote from scratch and are beginning with a short-block and heads, it’s nice to know that you can still buy everything new from Ford Performance Parts. This is the M-6580-M50-1 timing and cam cover kit, which includes everything, including idler pulleys and all hardware. Everything is here to button it up. (Photo Courtesy Ford Performance Parts)
Based on dyno testing at JGM Performance Engineering and a series of cam and induction system swaps, we’ve learned that you can make at least 100 more hp with a box-stock Coyote. The key is to choose a camshaft carefully based on the kind of driving you will do most of the time. Cam tech help lines can be very helpful, helping you to choose the right cam and spring combo. If you’re content with the factory’s Ti-VCT system, stay with it; and use phaser limiters when required. If you prefer to lock in valve timing, degree in the cams carefully along with a professional performance tune while you’re at it. In fact, a professional performance tune on a chassis dyno is something you must do any time you perform a cam and induction swap.
Written by Jim Smart and Posted with Permission of CarTechBooks
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