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.
Check out the photos for details on the install, but note it was much less difficult than we imagined. Once equipped with the new cams, we employed the SCT software to dial in the air/fuel mixture, and ignition and cam timing. Given the complexity and sheer number of drop-down menus on the factory computer, great care must be taken to ensure repeatable back-to-back runs. Ignition timing changes (for instance) required changes to every one of the 32 different ignition tables. The data logging was a valuable tool to ensure both cam and ignition timing remained constant for all of the testing.
After swapping the cams, the motor fired up instantly (always a good sign), then (after tuning) produced 498 hp and 441 lb-ft of torque. That represented gains of 36 hp and 31 lb-ft of torque, though the cams sacrificed small torque losses (15 lb-ft) below 3,900 rpm. Given our limited dyno time, it is possible that we may have been able to tune some of those losses back out, but even those were a small price to pay for the impressive gains through the rest of the rev range.
After running the cam test, it dawned on us that the Coyote was still equipped with a stock airbox. Given that an air intake is usually one of the first modifications made to a new 5.0L Mustang, it seemed only natural that we replace the stocker on our killer Coyote. JLT Performance was kind enough to supply an air intake system for the new Mustang.
The air intake featured a molded plastic air tube that easily out-flowed the stock box thanks to a sizable change in inside diameter, a gentle radius, and use of a free-flowing air filter. The combination was easy to install, but required tuning for optimized performance. Once installed, the motor produced 515 hp and an amazing 450 lb-ft of torque (an impressive specific torque output given the displacement).
Having bested the 500hp mark in normally aspirated trim, we starting thinking about what it might take to reach 600 hp. After all, we have ported heads, wilder cams, and even different intake manifolds yet to try. After that, we look forward to more boost with a turbo system, then possibly a forged rotating assembly, and even an increase in displacement. Stick around--our Killer Coyote is just getting started.
Ford Racing 5.0L-Stock vs. Comp Stage 2 Cams
The graph illustrates that the Comp Stage 2 cams offered some serious power gains. The cam swap increased the power output from 462 hp and 410 lb-ft of torque to 498 hp and 441 lb-ft of torque. There was a slight drop in power below 3,900 rpm, but we feel tuning may have reduced or eliminated the losses altogether. The big gains from 4,000 rpm to 6,700 rpm (and beyond) more than offset the small losses.
Stock vs. JLT Air Intake
After swapping the cams, we realized that the factory air box was still in place. We suspect the gains offered by the cams may have been even greater had we installed the air intake first. Regardless, installation of the JLT air intake in place of the factory air box netted sizable gains for such a simple bolt on. The JLT air intake improved the power output from 498 hp and 441 lb-ft to 515 hp and 450 lb-ft of torque. How cool is a 5.0L motor that pumps out over 500 hp (normally aspirated)!