The world’s fastest full-bodied, electric-powered drag car is the Mustang Super Cobra Jet 1800, developed by Ford Performance in the USA. On March 22, at the NHRA Winternationals at Pomona Dragstrip in California, the car, driven by Pat McCue, ran the quarter mile in 7.759 seconds at 180.14 mph, beating the 8.128-second time set by its predecessor, the 1400, four years ago.
Black Current 4 on the strip at Santa Pod
The next quickest is the Volkswagen Beetle-bodied Black Current 4 (BC4), privately developed by British brothers Sam and Olly Young of Current Racing. It set a best of 8.287 seconds at 163 mph during the UK’s Santa Pod meeting in August 2023. Considering the comparable budgets that are most likely involved, that is some fine effort.
The BC4 is a remarkable evolution of a car that started life as a cross between a scrap Beetle and an old, rusting milk float. The latest version, developed with support from the Young family's industrial and EV motor and accessories company, AmTecs, now uses Cascadia Motion electric motors and inverters, AEM controllers and bespoke battery technology – as does Ford Performance's Cobra Jet. And, right now, Ford Performance and the brothers Young are both seeking to reduce the world record time.
The new upgraded Ford Mustang 1800
The modest, yet very impressive BC4 has yet to show its full potential. Still in the relatively early stages of development, it could come to usurp Ford Performance. But, at the same time, the Super Cobra Jet 1800 has only just had its first outing, so there may be plenty more to come there too.
And so, the race is on: Beetle versus Mustang – David versus Goliath.
The Mustang
The first evolution of Ford Performance’s electric drag car, the Cobra Jet 1400, was unveiled in 2020, following a collaborative effort with MLe Racecars, AEM-EV, Cascadia Motion and Watson Engineering. It was based on the purpose-built Mustang V8 drag car, with the block replaced by an electric drivetrain comprising four double-stacked DS-250-115 motors coupled to four individual PM-250-DZR inverters.
The motors spun up to 10,000 rpm, with power transferred to a 1-to-1 SCS gearbox connecting the top and bottom motor stacks, providing a single-drive output to a T400 three-speed, air-shift transmission.
An engineer working under the bonnet of the Mustang 1800
Power management was achieved through an advanced data and control system, complete with a unique control algorithm jointly developed by Ford Performance and AEM-EV. The car had three BMS battery packs with total capacity of 60 kWh, which took three hours to charge using a dedicated generator. The temperature of the packs was performance-critical, so significant focus was placed on developing a complex internal and external cooling system to keep the batteries at a performance-perfect 35 C.
Aside from the electric propulsion, the car retained a relatively conventional rear-drive configuration, with a 9 in Ford rear, similar to the gas-powered 2019 Ford Performance Cobra Jet Mustang. Suspension was also familiar, although it used up-specced, adjustable Penske shocks to cope with the extra weight and torque from the electric drivetrain. Power was delivered to the track through a pair of 29.5 x 10.5 in Mickey Thompson drag slicks.
The car was not the first American factory-built electric drag car – that was Chevrolet’s one-off, 700 bhp eCOPO Camaro, which achieved quarter-mile times of about nine seconds – but this was on a different level. It delivered 1,502 bhp and 1100 lb-ft of torque, with the motor-inverter packages running at 800 V and up to 700 A, and a maximum output of 350 kW per motor.
A battery case located in the passenger seat area of the Mustang 1800
Ford promised to continue to develop this car, but the heavy battery pack, which topped it out at about 2.25 t, was a major obstacle. This has been one of the major focuses in the development of the new Super Cobra Jet 1800, which uses the exact same motor and inverter technology as used on the 1400, but runs it through a new transmission from Liberty.
It also carries an entirely new, lighter battery system, designed by Ford Performance and MLe Racecars. The car, which has the Ford Super Cobra Jet aero package with sealed front grille and MLe custom-fabricated rear wing, now weighs 1,980 kg without the driver, and it maintains the factory Mustang wheelbase of 107.1 in, with a weight distribution of 53.3% front to 46.7% rear. Precise details of the modifications are sparse, but the new machine has been described by Ford Performance as “an aggressive revision” of the previous 1400, with major work carried out on power delivery from the motors to the track via an MLe Racecars-revised rear end, featuring improved suspension geometry from PMR Race and Speed and 14.0 x 32.0 x 15 in Mickey Thompson drag radials to optimise the launch off the line.
The two-vertical, DS-250-115, 10,000 rpm double-stack motor layout, with four motors in total, was chosen as it fitted best within the Mustang chassis. The double stacks then feed into a summing gearbox to provide a single output to the driveline.
Ford explains: “Four motors in-line would not fit between the firewall and grille. Additionally, using a larger-diameter motor instead of summing smaller motors would result in high rotating inertia.” The 1800 uses larger ring gear – 9.5 in, compared with the previous 9 in – as the peak tractive effort has increased with this vehicle, and the increased gear size helps with durability when paired with the direct-drive system and larger tyres.
The new pneumatically-actuated Liberty transmission is a five-speed and capable of instant gear-ratio changes, which, Ford says, “helps us spend more time in the maximum power range of the motors”.
This transmission gives more flexibility with ratio selection and serviceability, enabling most changes and services to be done with hand tools in a trailer. The design also improves efficiency, trading the helical planetary gearsets and friction clutches for straight-cut gears and ramped dog clutches. The five-speed transmission only allows drive torque in its forward gears and will ratchet on coast due to its ramped dog clutches. This is highly preferred from a functional safety standpoint, and it allows the instant ratio changes by engaging two gears at once, with the transmission always engaging the highest gear selected.
The car runs at a maximum of 830 V and uses a Li-ion battery pack, a brand-new HV system made up of four discrete packs in series. Two packs sit behind the driver, one sits beside him (in place of a front passenger seat) and one is behind the front grille. In total, it provides 29.6 kWh of installed energy. The offboard heating and cooling approach is maintained for the battery system, with a traditional liquid-cooling circuit with radiator used for inverter cooling and air cooling for the motors.
There are some key upgrades to the control systems. The vehicle uses an AEM-EV controller with new high-tech proprietary control software and calibration, developed by Ford Performance. There is also a new data-acquisition system, dash and power-distribution system, all designed in-house. As the name suggests, power has been upped to 1,800 bhp, equating to 1,342 kW – an increase of almost 250 kW – while the chassis revisions and a lighter battery solution have shaved off “hundreds of pounds” in weight.
The increase in power is down to “several driveline improvements” to improve overall efficiency and a complete battery redesign “to reduce voltage sag and get maximum power out of the motor and inverters”, says Ford.
Ambitions for the new machine are high. After its initial record-setting run, Ford Performance hopes the Super Cobra Jet 1800 will continue to shave time off the quarter mile as the season progresses, with MLe Racecar’s co-founder and official programme test driver, McCue, once again in the driver’s seat. It could take some beating.
The Beetle
Compared with the Mustang, the background behind the Black Current Beetle is positively historic. The project started in 2003, at a time when Elon Musk was still four years away from launching his first Tesla Roadster. The idea came when brothers Sam and Olly wandered into their local scrapyard, and in a row of rusting wrecks they spotted an old VW Beetle sat next to a retired Morrison Electricar battery-electric milk float. In that moment, Current Racing was born.
The original orange milk float motor, sticking out of the rear of Black Current 1, with three motor contactors and the field-weakening resistor above
Olly recalls that the first creation was “a real Heath Robinson job to get it all going”. The two vehicles were morphed together, with the milk float motor going straight into the rear of the Beetle, coupled directly onto the original VW gearbox, fixed in second gear. Power was provided by a dozen 12 V FIAMM car batteries, connected by thick, copper wires, with welding cable feeding from the first and last batteries to the motor contactor.
Power was delivered in a binary on/off format, with the driver pulling a piece of string at the end of a simple contact switch to connect the main motor contact with the batteries.
Some limited control was achieved through the use of field-weakening resistors, salvaged from the milk float, which could be switched in to make the motor spin faster or slower, much like those used on the older London Underground trains.
The 144 V system’s motor was an old brush DC design, and Olly says there was little need to control it, as the more energy that was put in, the harder it would work. This rudimentary set-up proved to be a good learning base, but it only did a few runs, with a best quarter-mile of 21 seconds and a top speed of 55 mph, before it was retired in 2004. With no onboard charger, it would take too long to remove the 12 flat batteries and individually charge them up!
Black Current 2
Having sparked “quite a lot of interest” already, the brothers bought another Beetle – this time a 1973 former drag-racing version with roll cage and fibreglass front – and immediately set upon their next project. They sourced two 8 in-diameter, 72 V Advanced DC (ADC) wound DC electric forklift motors with large style comms and brushes. These were smaller, more compact and higher revving. The brothers put them in the rear end, one on either side, connected by a home-made, chain-driven, independent direct-drive gearbox.
Each motor had a small cog on its end, with separate chains connecting them up to a larger, central cog, going forwards in the car. This linked to the drive shaft and, again, there was no variable gearing, just one single fixed-ratio, but the speed was now controlled by a Café Electric 680 kW, 440 V Z2K-HV controller, and there was a real throttle pedal for the driver to play with.
Installation of the four-motor set-up on Black Current 4, extending rearward from the bulk head, with the motor output straight to the propshaft
Two battery banks containing a total of 40 motorcycle-derived, SVR-14, 12 V, lead-acid AGM batteries provided a range of one mile. They were located in the back seat and front passenger areas, with hosepipe-sized cables running to the controller and onto the motors. This time, the car did have a charger, a Manzanita Micro PFC-30, which delivered a rate of about an hour from empty to full – needed every three runs. The biggest challenge was the availability of parts, as electric vehicle development was still in its infancy.
To handle the current required, larger power-control capabilities were needed, and the controller that was used was the only one on the market. However, its power capability is “quite impressive”, says Olly, and it is still available today, although there is talk of ceasing production.
A 3D-rendered alternate view of the component layout for Black Current 4, showing battery, inverters, DC-DC, and main HV contactors and fuses
Just before a launch, however, a driveshaft snapped in a burnout and blew one of the motors, forcing a rush replacement, sourced from the USA. Tuning proved troublesome, and sparking issues caused a switch to a pair of higher-power ImPulse 9 series-wound, 72 V DC motors from a forklift.
The Black Current 2 motor set-up after it was upgraded
These did not exist when the car was first built, but despite the change, Olly says it was “still not very fast” and only achieved a 16-second quarter-mile run before being retired in 2008.
Black Current 3 (Version 1)
Work on the third iteration began in 2008, when the two ImPulse 9 motors were stripped apart and the parts used to make a compact, home-built, twin 9-in in-line motor with a single shaft, although this set-up was still limited in peak power by the continued use of the 680 kW Z2K controller.
The chain drive was ditched in favour of a Ford 9 in differential, typical of those found in many petrol-powered, drag-racing counterparts, and a small, two-speed overdrive gearbox, normally used on large American RVs for better fuel consumption. This was operated by a solenoid, changing gear in a split second using a button on the steering wheel.
The gearbox was coupled straight onto a prop shaft leading to the geared rear end that had a spool and a gear that could be exchanged for different ratios. This was connected to the car with four-link suspension. After struggling with grip on the previous car, the rear wheels were sized to give more, with 10 in-wide M&H drag slicks bolted on.
Again, when the car was first built, lead-acid with PC680 Odyssey AGM was the only affordable battery technology, and 40 of them were packaged up. After the first year, however, these were replaced by a 450-cell, lithium-cobalt pack when a cost-effective solution was found using 72 individual model helicopter batteries wired together. This reduced the battery weight by three-quarters, turning a two-tonne car into a one-tonner, while also providing 50% more power than the lead-acid specification.
All of that power proved useless though, because of limitations with the Café Electric 680 kW 440 V Z2K-HV controller that had been transitioned from Black Current 2. The device, says Olly, made it “hard to control the throttle” and, just like Black Current 1, it pretty much delivered its power as all or nothing.
“That made it very difficult,” Olly explains. “We couldn’t get it to go quickly in a controlled manner. It would launch off the line okay, go about 30 ft and then just light the tyres up.” The car struggled to get moving, virtually stalling when the motors started up, but once they reached 1,000 rpm they came into their operating window, delivering more energy.
“That’s where it would spin the tyres,” Olly says. “The motors developed more torque at a set rpm, so we tried to use the gearbox to flick the gear just before the motor got to peak power.
We got to grips with it, finessed things and kept going faster, but you had to know the car well to make it work.”
Black Current 3 (Version 2)
Trouble struck at Hockenheim in 2015, when the car suffered heavy damage due to a battery management failure that resulted in a lithium battery fire. Miraculously, the chassis, body and gearbox were rescued, and after a rebuild, a third motor was added to the existing in-line pair, with a second power controller added to run it. This pushed the car’s power level up to 1,360 kW.
In that configuration, Black Current 3 became the world’s quickest electric car and with that the first to dip under nine seconds, recording 8.282 seconds at 159 mph at Santa Pod in 2016. Despite that, the controllability issues persisted and, in an attempt to overcome them, the gearbox was switched to a drag-specific, three-speed B&J and CO2- shifter. The motors were modified to attach straight onto it, with no clutch or bell housing, and the driver could shift more times at the right power point.
It was that gearbox change, however, that ended the life of the car, when the CO2 shifting failed and it selected first gear at 140 mph at Santa Pod in 2017. The wheels locked and the car was sent into the wall. “That totalled it,” Olly recalls, adding that the driver, Sam, escaped from the incident unscathed and all of the onboard safety equipment worked exactly as expected.
“Unfortunately, we never really got to grips with that three-speed gearbox and that was the end of that car.”
Black Current 4 (BC4)
The latest iteration has gone to pro level, with a full, tubular chassis and carbon-fibre body, now in the shape of a 2013 Mk2 Beetle. This gives it a drag coefficient of 0.374 and a weight of 900 kg, distributed 365 rear and 535 front across the 2,560 mm wheelbase, although that overall weight will increase a little with the addition of a new gearbox this year.
Crucially, a switch from DC to AC motors means it now has far more precise electronic control than the previous machines, allowing the driver to manage torque throughout the rev range. To push power to the next level, the brothers upped the ante yet again with four in-line, three-phase, permanent magnet, axial-flux AC motors. These are from Phi-Power, built bespoke but with similarities to the Phi301.
Each motor is rated at 160 kW, giving a total power rating of 640 kW, and each can produce 530 Nm of torque from 0-4500 rpm before the torque drops off. The system’s total torque output is 2120 Nm, equal to 1,340 bhp at 4500 rpm.
Positioned in the middle of the car, where the gearbox would be in a V8 petrol machine, these motors are now 300 mm in diameter, rather than 9 in, and can run up to 10,000 rpm, with a nominal continuous total power output at 3500 rpm of 2120 Nm = 1000 bhp. They sit on a specially designed shaft that allows them to be stacked up, one in front of the other.
The drive is taken straight out of the back of the motor, with no gearbox, and the prop shaft leads down to a Ford 9-in axle, similar to that used in the previous car. Power is applied to the track through Mickey Thompson ET Street S/S P295 x 65R15 tyres.
There is now a compact 22 kWh lithium cobalt battery pack, built by Current Racing, with a total of 960 cells, made up from four blocks, with 192 x 4.2 V lithium cells in series. Olly explains: “During a run, the batteries are one of the limiting factors, so we carry a very small battery – a balance between power and weight.”
There are 16 individual battery management boards, created by EVParts, and a custom Chademo charger (up to 20 kW), also by EVParts. Safety protection is provided by, among other things, an insulation-monitoring device by Bender, ensuring nothing goes live on the chassis, indicated by Motorsport UK-regulated onboard red and green lights.
When it comes to keeping the battery at an optimum temperature, unlike the US-based Mustang, which needs special attention in the typically high climatic temperatures, the UK-based Beetle has a different challenge when running at a usually far cooler Santa Pod.
“We do not have cooling on the battery pack,” says Olly. “In fact, quite the opposite – we have battery heaters that ensure the batteries are at a nice, warm temperature!”
The BC4 runs at just over 800 V, double the previous level, due to the AC motor’s preference for higher voltage and lower current. There is one AEM VCU 300 controller, programmed specifically to monitor and deliver the required power. This separately controls all four three-phase Cascadia Motion PM150DZR water-cooled inverters, with each taking the DC input signal, chopping it up and rebuilding it into an AC waveform that is distributed to each motor to determine its performance.
After six years of r&d, the BC4 has so far only achieved an 8.287-second best at 163 mph, at Santa Pod in August last year. Olly concedes this is not much better than the old iteration, but he says there is plenty more to come. “This one feels a lot more in control. We spent nearly 10 years developing the last car, and we are only into our third on this now. Last year, we only had around 15 runs, but we started in the late nine seconds, so it is still evolving.”
The diff ratio is currently 5.29:1, but after modifying and testing different ratios and chassis setups, the brothers have discovered the AC motor does not have as much grunt as the DC to get off the line, but it does have more speed at the top of the track. However, drag racing needs grunt, so this year’s project is to fix the diff ratio – with an initial target of around 6.50:1 – and add a modified Gear Vendor overdrive gearbox with a ratio of 0.78:1. That, they believe, could offer a 20% improvement in performance.
So, this year looks set to be pretty exciting on the drag strips either side of ‘the pond’ as the assault on the electric record begins, with national pride at stake. This is the UK versus the USA. Both sides believe they can have seven-second quarter-mile times in their pocket, but which one will ultimately end up at the top of the record books? Stand back, because the atmosphere is… well… electric.