You are here
Home > FEATURES > Turbo Jet—The Twin Turbo Cobra Jet concept teased the potential of the quarter-mile performance path not taken

Turbo Jet—The Twin Turbo Cobra Jet concept teased the potential of the quarter-mile performance path not taken

Since its development and trade show tour, the Twin Turbo Cobra Jet concept remained in storage until it reappeared at the 50thAnniversary Cobra Jet Reunion

Written by Steve Turner

Photography by Kevin Diossi

A crowd forms around the stage at Ford’s well-placed display at the center of the action in Las Vegas. For a week, this is the center of the automotive aftermarket world. It is the SEMA Show, circa 2012. The Blue Oval’s performance division, which was at the time known as Ford Racing, was set to take the wraps off something special.

The excitement built like boost against a wastegate. Many who aren’t familiar with the layers between production vehicles and aftermarket-centric performance offerings expected a new production vehicle. Such reveals are often held back until traditional auto shows. The Specialty Equipment Market Association’s annual show is where people gather to learn about modifying cars beyond their stock capabilities and every company sets out to make a splash.

While much of this Cobra Jet mirrors its production, supercharged cousins, the Twin Turbo concept did have a unique livery, front grilles, and Weld Racing wheels.

Ford was about to do that in a big way by reveling a truly special vehicle. When the covers came off, it made headlines like no other vehicle at the show. It crossed over to mainstream automotive coverage and even garnered discussion as far and wide as massive Volkswagen messageboards. It was the kind of exposure most companies can only dream of and it came from pairing two things that we now know go so well together — turbochargers and Coyote engines.

“Ladies and gentlemen. Here it is, to my left, the all-new, 5.0-liter Twin Turbo concept car,” Jamie Allison, director of Ford Racing Technologies at the time, announced as it was revealed. “Designed for NHRA Super Stock competition the Cobra Jet concept car is capable of running well in to the 8-second (range). It is fast enough to put our customers in the winner’s circle. It showcases the next generation of drag racing technology and provides a glimpse of the potential future of the Cobra Jet program. And, I think the results will speak for themselves.”

Under the hood is where the magic lived. Two Borg-Warner EFR 7163 turbochargers fed a robust 5.0-liter engine based on the Sportsman block and topped by a unique Cobra Jet intake and Boss 302 heads fitted with supercharged CJ camshafts. With a big air-to-air intercooler feeding the oval-bore throttle body with boost, it delivered horsepower that likely exceeded 1,100 ponies. Interestingly, had this car made production, the prevailing thought was to eschew this setup in favor an air-to-water intercooler based on the extant supercharger’s intercooled lower intake and fed by two throttle bodies to balance the airflow.

As quickly as the announcement echoed across the Las Vegas Convention Center, the speculation had begun. Not only did enthusiasts expect the Cobra Jet to add turbocharging, but many incorrectly made the leap that a production Mustang V-8 might get turbos as well. Alas, as time went on, the Twin Turbo Cobra Jet concept met the same fate as many concept vehicles do. It never made it to production, but it remains an iconic vehicle in the modern Cobra Jet pantheon.

Fortunately, it reappeared during the 50thAnniversary Cobra Jet Reunion at the 17thAnnual Honeywell-Garrett NMCA All-American Nationals at Summit Motorsports Park in Norwalk, Ohio.

“The car was a huge success and very popular amongst Mustang and Cobra Jet fans. We still get questions about when we are going to build it! What better place than the ultimate Cobra Jet party to bring the car out and show it off again!” David Born, Parts Engineer at Ford Performance, said. “Folks loved seeing it again. It still brings out the questions on when we will put it in to production.”

There we were able to capture the concept Cobra Jet in all its glory, which inspired us to look back at how it came together — and what might have been.

Of The Moment

Longtime followers of Ford’s performance and racing endeavors may recall that around 2012 the Blue Oval was still introducing us to a branding that is now part of the zeitgeist — EcoBoost. To do so, many of its racing vehicles, even those running in the NASCAR and NHRA ranks, were switching over to EcoBoost-themed liveries denoted by a black stripes with EcoBoost blue accents.

Within Ford Racing, now Ford Performance, at the time, the team obviously wanted to capitalize on this look for the upcoming SEMA Show. Ultimately, after internal discussions, they determined to deliver what many enthusiasts had dreamed of from Ford — a turbocharged V8 Mustang.

Doing so for a concept vehicle designed initially for promotional value meant engaging in a skunkworks development process that drew upon the passion and excitement of the Ford Perfomance team, which became contagious amongst key players in other divisions to help with the process.

While the Weld Racing front wheels were the same as production Cobra Jets, the Twin Turbo concepts rear beadlock wheels featured custom Twin Turbo rings. Only three sets were created — two in black, which ended up on the final car, and one in EcoBoost blue. The latter didn’t make the cut because it wasn’t a direct match for the blue highlights in the EcoBoost livery.

Spearheading that development drive were Cobra Jet powertrain development engineer Rob Deneweth, former drag racing competition manager Jesse Kershaw, and engineer David Born, who eventually joined the team and brought turbocharging expertise learned in Ford’s mainstream engineering.

“Despite its smaller displacement, the improved breathing of the 5.0-liter with its twin independent variable camshaft timing and Boss 302 cylinder heads provided comparable performance while showcasing the high technology available in street Mustangs today,” Deneweth said at the time. “Ever since we re-launched the Cobra Jet in 2008, we’ve continuously evolved the engine to be more optimized for drag racing and produce more power for its NHRA class.”

“I recall back at the time Rob asking me if I wanted to be involved with the project. I had never participated in anything like that at the time so I jumped at the chance. In my past, I had been responsible for the engineering of the Boss intake manifold, so we developed the plan to take a unique dual-bore version (first used on the 2013 naturally Aspirated 5.0-liter CJ) and brand it for the TT car,” Born explained.

Team Effort

That chase for power built energized the team to create this concept project and draw on a wide variety of resources within Ford’s performance division and beyond.

“It was truly one of the great collaborative efforts during my time at Ford. For example, we didn’t have money to do a slow-mo shoot out at the track, so the guys who do the slow-motion cameras for accessory drive testing brought the camera to the track, and that’s how we got those slow-motion shots because they were so excited to be a part of it,” Kershaw told us. The guys at the rapid prototype lab cranked out those Twin-Turbo intake manifolds because they were excited to be part of it.”

The interior of the Twin Turbo Cobra Jet is a mirror image of the production CJs of this vintage right down to the Hurst shifter and Recaro seats.
A cool facet of the Cobra Jet interior is the prominent OBD-II port mounted in place of the passenger-side air conditioning vent. More interesting about the Copperhead PCM on the other end of this port is that engineers reprogrammed the software to run using speed-density engine management to ease the calibration of the turbocharged combination.

We can certainly see why they were excited. This project project the brought together two of Ford’s most exciting powertrain technologies and opened up some exciting possibilities for the future.

“Ford has embraced turbocharging technology and a lot of our production engineers are working with the technology on a daily basis, so we have a lot of knowledge,” Deneweth explained back then. “So we decided to apply that knowledge to the Mustang Cobra Jet to showcase what our engineers and suppliers know how to do.”

Essentially, the engineers used the same 5.0-liter engine that spec’d for the supercharged Cobra Jet, and set it up with an intercooled turbocharging system based on two Borg-Warner EFR 7163 turbos.

“Inside Ford, Dave Born, who is our turbo tech specialist was critical in working with the production supplier, Borg Warner, to get us a production based turbo that met our demands,” Kershaw told StangTV after the reveal. “Even with the hardware sorted out calibration proved difficult with a relatively small mass airflow housing diameter and lots of air coming through. We had a fairly short period of time to deliver but an exciting program like this gets people excited, we pulled together to make it a ‘one Ford’ effort.”

“In 2012, I was a design and release engineer for the 3.5-liter truck and 2.3-liter Mustang turbochargers. Rob also asked for my help with specifying the turbochargers for this car. He wanted them to be great performers, but also matched appropriately that the combo could be used for a street car, in case Ford Racing decided to pursue a catalog kit,” Born told us. “I was working closely with Borg-Warner on production programs and was very impressed with their OE capabilities. They turned me on to their race parts and worked with us to pick the right product. We selected the EFR-7163 from their EFR (engineered for racing) line of parts. It is a relatively small turbo from aftermarket racing standards, but would produce more than enough output to create a CJ beyond anything Ford Racing had done at the time.”

While these advanced, ball-bearing units offer higher performance that factory EcoBoost turbos, they still maintained internal wastegates like production turbos. However, these snails utilized titanium-aluminide turbines that cut rotational inertia in half and allow for the compressors to reach 150,000 rpm in the blink of an eye.

While the Twin Turbo Cobra Jet was a path not pursued, it remains a noteworthy achievement for Ford’s performance division, and the late engineer Rob Deneweth, who helped spearhead its development.

Turbo Testing

“When done right, turbocharging is just as good as or better than supercharging,” Born explained back then. “To overcome the biggest perceived drawback of turbocharging — the lag — we’ve selected the smallest possible turbos that will give us the airflow we need,” he added. “We’ve also got some other enhancements to help improve the responsiveness; we have very low inertia and very low internal friction.”

The pairing of two turbos and a robust Coyote 5.0-liter resulted in four-digit horsepower, but the team needed vehicles to test and showcase the cutting-edge powerplant. To do so, the team drafted two 2013 Cobra Jet test vehicles that had served time developing the naturally aspirated versions of the prior Cobra Jet powerplants. The white car was built to fruition with the full turbocharged powertrain, while the black car served as the model for the concept’s brochure.

As the 2012 SEMA Show approached, time was tight. In order to execute the testing, photos, video, and brochure in time for the show, the white car headed to the racetrack with Watson Engineering’s Kim Mapes manning the wheel, while the black car headed for the photo studio. Some of the one-off parts for the vehicles were in short supply, so they had to be shuttled between the two locations on the same day.

There are some interesting tidbits about this unique concept vehicle. Firstly, the font used for the Twin Turbo font on the hood and fender is not exactly the same as the one used on the rapid-prototype intake manifold. The telltale sign is the dot over the “i.” The dot on the intake is round, while the dots on the exterior are squares. Also of note is the low-hanging turbo location on the concept. This location resulted in oil-seal failures. Had the car moved to production, the turbos would have been moved up by a foot and drawn inlet air from the corners of the front grille.

Despite the pressure of prepping for he reveal and a torque converter that wasn’t optimized for the turbo combo, the white Twin Turbo Cobra Jet made a series of test hits. Most were 60-foot and 330-foot rips for the cameras, but two full eighth-mile blasts were run. The best of the two was a 5.4-second run, so the potential was clear. Only high-8-second potential was promised at the show, but clearly the lighter turbo combo could easily have eclipsed the supercharged version by a couple tenths.

Show Of Force

With the testing and promotional imagery in hand, the Twin Turbo Cobra Jet was prepped and shipped to Las Vegas for its big show reveal. The white car displayed at the SEMA Show was the same one that had run during the drag testing video shoot. A complete turbocharged 5.0-liter engine on a display stand accompanied the concept car for maximum impact.

As previously noted, the car definitely served its purpose of polishing the Blue Oval. Performance enthusiasts across the world were rapt by the possibilities of a twin-turbo Coyote ripping down the drag strip. It set the stage for a new path for Ford’s factory-prepped drag racing star car.

“With more NHRA records and wins than any other late-model vehicle, the Cobra Jet is the standard in production drag racing and the Twin Turbo concept provides a glimpse of what the future may hold through Ford Racing,” Allison was quoted in the brochure. “Others may build racecars, at Ford Racing we engineer a Cobra Jet. Go Ford!”

Moreover, Ford’s on press release promised that Deneweth and Born would “continue to develop both the performance and durability of the twin-turbo Cobra Jet.” Obviously there was an eye toward building this combination for NHRA competition.

Production Potential

That continued in earnest with the team that spearheaded its development pitching the Twin Turbo version to oust the incumbent supercharged combination. The combination had even been tentatively approved by the NHRA, so the path was clear for it to become a reality if the dollars and cents added up.

“Hours of debate on the subject has been had within Ford Racing/Ford Performance Parts,” David recalled. “The performance potential of the car, at the time, was well beyond what we were producing for customers. It would have meant that car would need to be placed in Super Stock, while our effort at the time was focused on Stock Eliminator. It would have required increased safety measures and increased testing that, at the time, we weren’t prepared to take on.”

However, at this pivotal moment of debate, tragedy struck. One of the prime proponents of the Twin Turbo Cobra Jet, and its engineering leader, Rob Deneweth took his own life just three days after it was pitched as the next Cobra Jet. It was unexpected and deeply saddening news for all those who knew Rob. Ultimately, it also meant that this Cobra Jet would remain a concept. Its development died with him, but the achievement of the car you see here lives on as an iconic machine and a testament to his engineering prowess.

“I recall Rob saying that this was his favorite project he had completed,” Born said. “And that’s saying a lot given his involvement is the other Cobra Jets and road race cars he had worked on, not to mention his forward model programs in his past, including the ’03 Mach 1 as an Engine Programs Engineer.”

“I he think was extremely proud of it,” Kershaw reflected. “He went out to SEMA and had a great time representing the car. He leveraged a lot of his relationships inside Ford Motor Company to make that car happen. If he wasn’t proud, I don’t think he would have done that.”

So, the Twin Turbo Cobra Jet never made production. It was replaced in that year’s NHRA rulebook by a supercharged combination with a smaller 3-inch pulley, and the car has been in storage until it reappeared during the 50thAnniversary celebration, reminding us what could have been.

And, who knows, maybe one day there will be another turbocharged Cobra Jet, but this concept will remain a part of the storied brand’s lore for years to come.

The Black CarObviously the white version of the Twin Turbo Cobra Jet made the biggest splash, appearing on the big stage at the SEMA Show and making those drag strip runs on the video that Ford released back in the day. However, there was that black version that appeared in all the marketing flyers and press releases.

The engine designated for the black car was the one that appeared on the engine stand at the show. It was never installed or run in the black car. As such, it was never really completed. Eventually it was parted out and sold. However, it has not been lost to the history books. Instead a private collector has fastidiously gathered up the car and all the parts, including that display engine, necessary to complete the second and only other Twin Turbo Cobra Jet in this elite bloodline.

Paying Tribute

If you were at the 50thAnniversary Cobra Jet Reunion, you might have done a double-take. Not only was the original Twin Turbo Cobra Jet concept on display with a host of other iconic CJs, it also had a doppleganger that was making passes on the drag strip. With the hood down, it would be tough for the casual enthusiast to tell the two apart, but the lookalike was is actually a replica commissioned by Michael Szmytke at Buy Ford Racing to honor the memory of Rob Deneweth.

The fabrication work for this car was completed alongside other Cobra Jets at Watson Engineering, while the rest of the build was completed at Walsh Motorsports. Mat Brunette at Billet Pro Shop bought the car at auction, after initially mistaking it for the original.

“…We later found out it was a tribute but the amount of detail and quality put in this build was all worth it,” Mat explained. “Mike was a good friend of Rob’s; after his passing he decided to build a car in memory of him. Being the powertrain engineer behind the TT project, Mike had no choice but to build just that, a Twin Turbo Cobra Jet.”

What began as a Body In White was upfit to Cobra Jet specs for the 2013 model year and finished off with a 9.5:1 Aluminator engine boosted by a Hellion Power Systems Eliminator twin-turbo system. Brunette plans to grudge-race this beauty, so the performance specs are on the down low, but it definitely draws a crowd wherever it goes.

“Just like ourselves at first, many thought it was the real deal,” he said of the car’s reception at the 50thAnniversary Reunion. “We got a lot of ‘This is what the CJs should have come with.’”

The Details

Owner/Driver:Ford Performance

Hometown:Dearborn, Michigan

Occupation:Going fast

Class:NHRA Super Stock A

Car Make/Model/Year: 2013 Cobra Jet

Engine:V8 with Twin independent Variable Cam Timing

Engine Builder:Ford Performance

Displacement:5.0 liters

Block:Ford Performance experimental

Bore:92.2 mm

Stroke:92.7 mm

Crank:Forged steel

Rods:Manley H-beam

Pistons:Mahle forged, built to Ford Performance specs

Heads:CNC-ported, four valves per cylinder

Valvetrain:Twin Independent Variable Cam Timing

Cam Type:Custom Ford Performance proprietary grind

Intake:Rapid-prototype Cobra Jet intake manifold with Cobra Jet oval monoblade throttle body and carbon fiber inlet tube

EFI System:Copperhead PCM with Ford Performance calibration for speed density electronic fuel injection and 8,100-rpm rev limiter

Fuel System: Aeromotive Eliminator fuel pump with Aeromotive A1000 pressure regulator, Aeromotive 10-micron high-flow filter, and high-impedance 80 lb/hr fuel injectors

Power Adder:Two Borg-Warner EFR 7163 turbochargers

Headers and Exhaust: 304 stainless primary tubes with 321 stainless collectors

Transmission:C4 automatic

Transmission Builder:Race-prepared by Joel’s on Joy

Shifter/Torque Converter: Hurst shifter and Joel’s on Joy converter

Rearend:Strange Engineering 9-inch aluminum center section with lightweight steel spool, Strange Engineering 9310-alloy 4.88 gears, Strange Engineering 35-spline axles and a Strange Engineering chrome-moly yoke

Body and/or Chassis Builder:Ford chassis with chrome-moly safety cage, NHRA-certified to 8.50 ET

Suspension (Front):Adjustable Ford Performance struts, anti-roll bar removed, and lightweight radiator support

Suspension (Rear):Three-link with adjustable upper arm, adjustable Panhard bar, double-adjustable Ford Performance shocks and rear anti-roll bar

Brakes (Front):Strange Engineering with lightweight, vented rotors; billet, four-piston, lightweight calipers; lightweight tandem master cylinder, and an OEM pedal modified to mount master cylinder

Brakes (Rear):Strange Engineering with lightweight, vented rotors

Wheels (Front):Weld Racing Twin Turbo Cobra Jet, 15×3.5-inch

Wheels (Rear):Weld Racing Twin Turbo Cobra Jet beadlock,15×10-inch

Tires (Front):Goodyear Cobra Jet, 4.5x28x15-inch

Tires (Rear):Goodyear Cobra Jet, 9x30x15-inch

Quickest ET:Projected mid-8-second quarter mile

Fastest MPH:Projected 155 mph

Sponsors:Ford Performance