“Peak Analogue” is what the team at the British company Boreham Motorworks attempts to capture with all of its machines. As for the way the spec sheet reads for the firm’s latest creation, you’d be hard-pressed to find any reason that it’s missing the target. The company describes the powerplant’s sound as “sharp and vocal,” which gets the hair on the back of a gearhead’s neck to stand on end.
Harnessing this philosophy, Boreham Motorworks builds the Ford Escort Mk1 RS, a continuation model licensed by Ford. It plans to craft 150 examples for the entire world. The vehicle is not designed just to invoke memories of the past, but to honor the classic model in the present by adding modern touches. One of the upgrades is a 2.1-liter four-cylinder producing 325 horsepower and capable of revving to 10,000 RPM.
We Can’t Get Enough Of This Naturally Aspirated Four-Cylinder
Boreham Motorworks MK1 Ford Escort RSBoreham Motorworks
With 325 hp from a 2.1-liter four-cylinder, the Boreham Motorworks Ford Escort Mk1 RS makes roughly 155 horsepower per liter of displacement. The figure is impressive for a naturally aspirated powerplant. For example, the Honda Civic Type R has 315 hp from a turbocharged 2.0-liter engine, meaning it has 157.5 per liter. Mercedes-AMG achieves 200 hp per liter from its 400-hp turbocharged 2.0-liter four-cylinder in the Lotus Emira.
To release all 325 hp from Boreham’s twin-cam TEN-K 2.1-liter engine, a trip to the 10,000-RPM redline is required. The 3D-printed engine block, with thin cylinder walls for weight savings and better cooling, contains featherweight forged billet steel internals. The crankshaft and connecting rods are made from this material, working in conjunction with a single-mass flywheel and twin-plate clutch assembly to limit rotational inertia. The weight savings pay off since the entire engine weighs just 187 pounds (85 kilograms).
It makes peak torque at 6,500 RPM, with the rest of the power hanging on through the remaining 3,500 RPM left before hitting the redline, translating to a strong, enticing pull that conveys a greater sensation of acceleration as the engine gets louder.
Along with its lightweight guts, Boreham is proud of its 16-valve cylinder head designed with “F1-inspired” combustion chamber geometry. There are also individual throttle bodies, which quicken the response of mechanical components to make power the instant the throttle is tapped. The dry sump design of the engine saves weight and permits a lower mounting point in the body, which, without the powertrain, weighs 1,785 pounds (810 kilograms), keeping the complete package of this Escort RS to a sub-2,000-pound curb weight.
Turbocharging was never part of the plan for this engine. All the lightweight pieces in the engine were designed with a weight-conscious mindset that combined with the naturally aspirated formula to deliver one special package.
We’re looking for a very visceral driving experience—something that’s memorable, which means instantaneous performance.
– Laine Martin, Head of Powertrain at Boreham Motorworks
Both the reaction of the engine and the sounds that follow are part of the experience; qualities that Martin wanted to incorporate into the Escort RS from the start. “A naturally aspirated engine gives us both the intake and induction noise, and a really nice exhaust note.”
As for the Formula-One-derived technology that made its way into the TEN-K, Martin used the high-revving engines of the 2000s as the source of inspiration for the porting and combustion chamber designs. Prototypes returned impressive performance on the dynamometer and fulfilled Martin’s requirements for the engine.
Installing road-going components like the exhaust and intake manifolds suppressed the absolute performance observed on the dyno. However, Martin maintained the project’s roots in bringing modern racing technology to this classic vehicle.
Modern Nostalgia: How the Escort RS is the Best of Both Worlds
Boreham Motorworks MK1 Ford Escort RSBoreham Motorworks
Since all but a few of the 150 examples of Boreham’s Escort RS are new cars (with some delivered as a restomod depending on the market) built from the ground up, there are a few modern elements to make them compliant today. The intake and exhaust are just two facets of compliance with government-issued non-negotiables. A fly-by-wire throttle system is there to “enhance the character and feel” of the already rev-happy TEN-K motor, according to Martin, and can be tuned for different throttle progression settings.
The powertrain and chassis work together to deliver Boreham’s trademarked tagline. The lightweight construction and where the mass of the drivetrain sits have been worked out, bringing dynamics never seen before in the original Escort. The engine sits as far rearward as it can while maintaining the required clearance off the firewall. The gearbox is as far back as the transmission tunnel allows, with the main goal to keep the center of gravity as low and as far back as possible in a front-engine, rear-wheel-drive car.
Perception of Performance: Building a Car to Evoke the Senses
Boreham Motorworks MK1 Ford Escort RSBoreham Motorworks
All this brings to mind some of the other important sports cars that use zingy, high-revving naturally-aspirated four-cylinders. The Toyota GR86/Subaru BRZ twins in both their current and former presentations. Not to mention, the Honda S2000 and anything carrying Toyota’s 2ZZ-GE engine are each remembered for the character of their powertrains.
Honda’s F20C and F22C1 four-cylinder engines used in the S2000, along with Toyota’s 2ZZ-GE four-cylinder, used variable valve timing to adjust the camshaft profiles, thus changing how and when the engine creates peak power. The S2000’s early engine famously could rev to 9,000 rpm. Toyota’s mill can spin to 8,500 rpm. Making power that way works when manufacturers are on a budget, but since Boreham is clearly not, it affords them the creative opportunity and budget to dip into the parts bin marked for race cars.
All the lightweight, billet steel components that cut rotational inertia and save weight mean the TEN-K doesn’t need to use adjustable valve timing tactics to change the engine’s dynamics. VVT can split an engine’s personality, only becoming highly responsive after the change has been made. Lightweight materials incorporated from the start mean the tail can wag right from the start.
Has Boreham Delivered on its Claim to Fame?
Boreham Motorworks. Ford Escort Alan Mann 68 EditionBoreham Motorworks
The firm had a lot of practice building Escorts the way Ford first did in the 1960s to go racing before it started work on the RS. The company produced 24 licensed continuation Escort models designed and built with Alan Mann Racing, all of which are period-correct Group 5 touring cars ready for the track. Needless to say, the business knows its way around the Mk1 Escort.
Even without driving the Ford Escort Mk1 RS, it’s clear the work was put in to fulfill the plans outlined for the project, and the company’s philosophy of being as analog as possible. The RS will be something that catches the eye of millionaires with classic taste and a passion for modern mechanics. Other cars you can shell out the same coin for have twice the performance with half the character, which places Boreham’s creation in a league of its own, with a price roughly equivalent to $394.480 (£295,000).
At the core of what makes classic cars appealing are the sounds and smells that modern cars limit as much as possible. The Escort RS needs no alchemy to trick drivers into believing it’s powerful. But the way it creates its power, the way it sounds as the revs climb, and the pull it holds throughout the gears are all inherent qualities it was designed to have.
Sources: Boreham Motorworks
