Muscle Mustangs & Fast Fords
Mods for Coyote Mods, Part 3 - Back To Bolt-Ons
Camming A Naturally Aspirated Coyote Crate Engine
Looking back at the two previous installments of "Mods for 5.0L Coyote Mods," we see that the Four-Valve motor has come full circle. Starting with a 5.0L Coyote crate motor (PN M-6007-M50) and complete Controls Pack from Ford Racing Performance Parts, we first applied a few simple bolt-ons, then went whole-hog in Part 2 with boost from a Kenne Bell supercharger.
The FRPP crate motor was essentially a stock 5.0L destined for a '11 Mustang GT. The Controls Pack included ECU and wiring harness, MAF and air intake system, factory airbox, OBD-II diagnostic port, drive-by-wire throttle, and a complete calibration.
Run on the dyno in as-delivered trim, the motor produced 448 hp and 405 lb-ft of torque. Headers increased this to 462 hp and 411 lb-ft, while a small shot of Zex nitrous pushed things to 554 hp and 540 lb-ft of torque. Adding the supercharger resulted in 704 hp and 549 lb-ft of torque at just under 10 psi of boost. Equipped with the KB, the killer Coyote was impressive indeed, but off it came to make way for our trip back to bolt-ons.
Given the impressive performance of the 5.0L Coyote, we decided to get our hands dirty and dig into the hard parts, namely the camshafts. Unlike previous Four-Valve mod motors, the Coyote was blessed with variable cam timing on both the intake and exhaust cams. The previous 4.6L Three-Valve also featured variable cam timing, but the intake and exhaust were not adjustable independently. The ability to advance and retard cam timing greatly improved average power production, but the factory Coyote cams were still on the mild side for maximum power.
Knowing the stock heads flowed nearly 300 cfm, it seemed like the Coyote was begging for wilder cam timing to take full advantage of all that wonderful airflow. Leafing through the Comp Cams catalog, we came across the perfect set for our otherwise stock motor.
Not wanting to change valve-springs, we selected a set of (PN 191100) Stage 2 NSR cams (no springs required) that offer a 0.492/0.453 lift split, a 228/231 duration split at 0.050 and a 126-degree lobe separation angle (with cams fixed—this was obviously adjustable). These compare to a 0.472/0.433 lift split, 211 degrees of duration (both intake and exhaust) and a 131-degree LSA for the stock cams.
There has always been a certain apprehension among enthusiasts when it comes to cam swaps on mod motors. The overhead design has many spooked, but the reality is that it is no different (or difficult) than a cam swap on a conventional motor. The installation instructions provided by Comp for both the phaser limiters and NSR cams made things even easier—even for the first timer (which we were).
Though we had plenty of experience with mod motors, this was our first adventure ripping into a new Coyote. Installation of the Stage 2 NSR cams required use of phaser limiters. The limiters were needed to reduce the amount of cam phasing from 50 degrees to 25 degrees. The reason for limiting the adjustable cam timing was to maintain proper piston-to-valve clearance. The clearance is not an issue with mild factory cams, but the system limits how aggressive you can go on cam timing with aftermarket performance grinds. The majority of the variable cam timing is done at idle, cruise, and part-throttle, as cam adjustment at WOT is considerably less than the available 50 degrees. Thus, the phaser limiters allow 5.0L Coyote owners to run performance cams with increased lift and duration without fear of piston-to-valve contact. It was (of course) necessary to adjust the software to reflect the limited cam travel, but SCT software allowed us to dial in all of the many variables on our modified test motor.