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ForTehNguyen
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"Aside from making it fit into the new platform, Ford’s seemingly impossible goals were to make the S550 GT’s V8 not only more powerful, but also cleaner, and even more fuel efficient than its predecessor.
Think of the result as something of a cross between the original Coyote and the Boss 302’s RoadRunner, with a bunch of new stuff thrown in. On the bottom end, the RoadRunner contributes its sinter-forged connecting rods—but not its forged pistons—to the S550’s Coyote. Instead, the pistons remain hypereutectic, with slightly revised valve clearance notches because of—you guessed it—slightly bigger valves. Compression remains at 11.0:1, while the forged-steel crank is rebalanced to accommodate these rod/piston changes.
The S550’s cylinder heads are all-new castings designed to recreate the RoadRunner’s deep breathing abilities without the need of that engine’s expensive CNC porting process. The intake ports are revised to take maximum advantage of both the larger valve package and the new engine’s lumpier camshafts. The exhaust cams are essentially RoadRunner bumpsticks, good for 13mm of lift. The all-new intake cams now also produce 13mm lift (even more than the 12mm of the Boss 302’s intake cams). Valve springs are stiffened accordingly.
Of course, the timing of those cams is variable, and Ford’s latest trick in that regard is a mid-lock timing phaser on the intake cams. Where previous setups traditionally had the intake cams fully retarded on start-up, the mid-lock strategy provides a more advanced start-up cam timing that improves cold-idle stability, economy, and emissions. The setup also provides more range of authority on intake cam timing, ultimately permitting better cruise fuel economy.
Up top is a new intake manifold. While quite similar in design, runner length, and height to the S197 Coyote intake, the new manifold bristles with Charge Motion Control Valves and their actuators. These valves introduce tumble and swirl into the airflow at part throttle, maximizing combustion efficiency."
Think of the result as something of a cross between the original Coyote and the Boss 302’s RoadRunner, with a bunch of new stuff thrown in. On the bottom end, the RoadRunner contributes its sinter-forged connecting rods—but not its forged pistons—to the S550’s Coyote. Instead, the pistons remain hypereutectic, with slightly revised valve clearance notches because of—you guessed it—slightly bigger valves. Compression remains at 11.0:1, while the forged-steel crank is rebalanced to accommodate these rod/piston changes.
The S550’s cylinder heads are all-new castings designed to recreate the RoadRunner’s deep breathing abilities without the need of that engine’s expensive CNC porting process. The intake ports are revised to take maximum advantage of both the larger valve package and the new engine’s lumpier camshafts. The exhaust cams are essentially RoadRunner bumpsticks, good for 13mm of lift. The all-new intake cams now also produce 13mm lift (even more than the 12mm of the Boss 302’s intake cams). Valve springs are stiffened accordingly.
Of course, the timing of those cams is variable, and Ford’s latest trick in that regard is a mid-lock timing phaser on the intake cams. Where previous setups traditionally had the intake cams fully retarded on start-up, the mid-lock strategy provides a more advanced start-up cam timing that improves cold-idle stability, economy, and emissions. The setup also provides more range of authority on intake cam timing, ultimately permitting better cruise fuel economy.
Up top is a new intake manifold. While quite similar in design, runner length, and height to the S197 Coyote intake, the new manifold bristles with Charge Motion Control Valves and their actuators. These valves introduce tumble and swirl into the airflow at part throttle, maximizing combustion efficiency."
MRGTX
Well-Known Member
Great info!
So for those pushing these motors with FI, are the pistons now the weak link in the motor?
Did they upgrade the oil pump gears from the original Coyote?
Was the uneven cooling ever addressed (that led to some #8 piston failuires)?
So for those pushing these motors with FI, are the pistons now the weak link in the motor?
Did they upgrade the oil pump gears from the original Coyote?
Was the uneven cooling ever addressed (that led to some #8 piston failuires)?
Grimace427
Well-Known Member
The oil pump gears have always been the weak link and they continue to be with the 2015. Pistons will crack with detonation from poor fuel or a bad tune. The cylinder #8 issue had nothing to do with cooling but rather tuners being new to the Coyote.
Todd15Fastback
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Yes, correct.
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