The Coyote 5.0 engine was the shot heard 'round the performance world. From the streets to the tracks, Ford's TiVCT-equipped V-8 has jumped to the forefront of modern performance. When it comes to the ultra-competitive world of the National Hot Rod Association, it was Ford Racing's modern version of the Cobra Jet that made the same kind of noise on the dragstrips of America.
Till this point, the '08-'12 Cobra Jets ruled the 1,320 with a powerplant based on the Shelby GT500's 5.4-liter engines. Variants boosted by both the familiar 2.3-liter TVS supercharger and the massive 4.0-liter Whipple supercharger have propelled the modern-day CJ's to great success in the NHRA's Sportsman ranks.
Fast-forward and the 5.4 is looking a bit weathered, as the Coyote 5.0 and new Trinity 5.8 set the modern standards for street performance. It certainly seems like it's time to make a change under the hood of the '13 CJ, and that's just what Ford Racing has done. Eschewing the proven 5.4 powerplant, Ford Racing engineer's steeled the modern-day 5.0 for the rigors of quarter-mile combat. Rather than beginning with the base 5.0, these engineers springboarded off the best that the mainstream engineers had to offer--the RoadRunner engine from the Boss 302.
And, why not? The 302ci engine from the Boss 302 already features CNC-ported heads, a high-revving manifold, and rugged internals. It seemed the natural jumping-off point for a racing engine program. So as a baseline, the Ford Racing crew started with a 12:1-compression version of this engine, and opened it up on both ends with its own 90mm throttle body and American Racing Headers long-tube headers. This combination was used to baseline the power level so they could iterate modifications to see what worked and what didn't.
Initially, some of the common hot-rodding tricks just didn't deliver. An electric water pump allowed cylinder head temperatures to rise enough that the Copperhead PCM started reeling in the timing. The same could be said of restricting water flow. Likewise, Ford Racing and several of its partners tried to best the performance of the stock RoadRunner cylinder heads--to no avail.
You would be smiling too if...
You would be smiling too if your job was building fast race cars with the support of the factory. Such is the case with our tour guide through the impressive world of Coyote-powered Cobra Jets, Ford Racing Powertrain Engineering Supervisor Robert Denewith.
The Cobra Jet engine program...
The Cobra Jet engine program underwent substantial testing by Ford Racing dyno operator Mike Simons. His dyno was built to verify the likes of Formula One and NASCAR engines. In the case of the naturally aspirated 5.0 CJ engine, it saw over 100 hours of testing. Here Rob Denewith and Jesse Kershaw discuss some of the results.
Boring and sleeving the Cobra...
Boring and sleeving the Cobra Jet blocks is specialty work, and Ford Racing calls on Livernois Motorsports for the equipment and expertise to deliver blocks with 94mm bores. These bores are achieved using the same sleeves used in the T50 Cammer program that deliver 5.0-liter engines based on the Four-Valve 4.6.
"We did our own CNC head. We actually got unported Boss heads. We were going to develop a Ford Racing head. Basically, from interfacing with the mainstream guys, we knew it would be difficult to get more power without putting bigger valves in it," said Robert Denewith, Powertrain Engineering supervisor at Ford Racing.
As it turned out, the mainstream guys were right; several companies tried to better the head via porting and didn't. The move to larger valves was deemed cost-prohibitive, but on the cam side of things, the work was already done on the Boss.
"We tested some camshafts. The original Boss program had a 13mm-lift intake cam. That was pulled out of the program and they went back to a 12mm, so it's a common intake cam. We kept the original Boss intake cam in the Cobra Jet and we're going to offer it for sale in the catalog. We're using the stock Boss 260-duration intake cam, and then we are using a 290-duration exhaust cam that we developed with the mainstream guys. We're selling that cam as well," Robert explained. "All the acceleration, ramps, and loads on the valvetrain meet our 150,000-mile durability. That's how all our cams are today."
It's obvious the mainstream engineers were really pushing the development envelope on the production parts. They also had some more radical ideas floating around that didn't quite make it to the assembly line.
Here is a block after its...
Here is a block after its been machined at Livernois. The naturally aspirated blocks are sleeved to 94 mm, while the supercharged blocks retain the stock 92.2mm bore. While the NA combo needs every advantage to maximize power, the supercharged combo must emphasize durability.
Like the Boss, the CJ 5.0...
Like the Boss, the CJ 5.0 doesn't make use of piston-cooling oil squirters. In fact, sometime during '12 production, all 5.0 blocks eschewed the plumbing for these jets. Surprisingly the CJ engines rely on lots of stock parts, including head gaskets and most of the fasteners. One area that is worth some power is the deeper sump in the CJ oil pan.
Here are the carefully orchestrated...
Here are the carefully orchestrated guts of a Cobra Jet 5.0 engine. Much of what is used in these engines has been proven in the 5.4-liter Cobra Jet and 5.0 Boss 302R programs. These internals are designed for maximum durability at a reasonable cost.
Both the NA and supercharged...
Both the NA and supercharged versions of the Cobra Jet 5.0 use a forged piston from Mahle Motorsports. Obviously, the naturally aspirated version features a larger bore (shown), while the supercharged version features a dish to deliver 9.5:1 compression.
There's really nothing special...
There's really nothing special about the rings and bearings in the Cobra Jet 5.0. These are the same factory parts proven in the Cobra Jet 5.4.
We all know that the rod is...
We all know that the rod is the place to upgrade a modern modular, and in the case of the Cobra Jet 5.0, it's a familiar Manley H-beam rod that first gained acclaim in the innards of the Terminator 4.6. While an I-beam rod was considered, it was deemed too costly and, really, unnecessary for this power level.