The Phantom story dates back 51 years to 1973, when Jaguar engineers Chris Greville-Smith and Richard Cresswell built their first Clubmans car. Cresswell won his class in the 1974 Silverstone-based Tricentrol championship, but CG-S – who subsequently transferred to Ford – continued the project solo, racing and developing his chassis and building a handful more, among them the ex-Kimber Crossley/David Childs P79 still raced by Steve Chapman.
Arguably the most consistent challengers to Mallock’s offerings over the period, Phantoms were subsequently created by several firms, including John Maguire Racing in Coventry, before being taken over by Jan Nordgren in Sweden, from whom Alex Champkin acquired the project. Greville-Smith still engineers cars, helping recent Brands Hatch race winner Michelle Hayward in Tom Commander’s Zetec-engined P82TR.
Having polished wheels as a lad for Clubmans racer dad Jamie Champkin – now Motorsport UK’s legal eagle – Alex evolved a Vision chassis before starting his mainstream business VMEP [Vision Motorsport Engineering Products]. Initially, it made chassis set-up floors, air jacks and pit equipment, but is now a market leader in bespoke flight cases for race teams and other industries which rely on secure transportation of precision equipment worldwide.
Since bringing Phantom back to Warwickshire, close to its Coventry birthplace, Champkin won the MSVR-badged Clubmans Register CSP1 championship in 2022 with Ford Zetec power. In 2023 there was double success running James Clarke in the existing CSP1 car and Mathieu Gaulthier-Thornton to the CSP2 crown with Rover motivation.
In a four-category structure split equally between historic and modern concept front-engined sportscars, the Clubmans Register’s front-running P1 division’s regulations provide the same scope for innovation as the original BRSCC’s Clubmans did when Nick Syrett introduced a competition for Lotus 7-type cars in 1965.
The motorcycle-engined option appealed to Alex Champkin and ignited the enthusiasm of Ashley “Captain Aerospace” Pearce, whose first automotive passion remains bikes. He joined VMEP as a welder, but has brought his skill set and instinctive know-how to creating and detailing the PR24.
Phantom boss Alex Chamkin (left), and Ashley Pearce have brought the PR24 to life
Photo by: Joy Batchelor
Lightning quick from its debut at Castle Combe in August, Champkin won both races, leaving a blistering 1m05.119s (102.14mph) lap record as evidence. A month later the combo completed a hat-trick in the wet at Oulton Park, then added a Brands double for a five-from-seven win rate.
Chassis
The tubeframe chassis, fabricated in-house by Pearce, is based on the previous PR22s, but the Suzuki engine/gearbox is mounted significantly further back within its wheelbase. But for a ‘power bulge’ in the bonnet’s flank, different water radiator requirements and greater oil cooling – fed by twin nostrils in the nose – the PR24 retains the distinctive low-slung Phantom look.
To optimise handling given the revised front/rear weight balance, the chassis requires greater rake than conventional versions. Another frame is on the stocks for 2025 delivery.
Engine
1340cc engine powering the PR24 revs to 11,000rpm
Photo by: Joy Batchelor
Built by racer Richard Webb’s renowned RLM Racing concern in Leicestershire, the engine selected for the Phantom application is 1340cc capacity, with stock internals, although some rivals use 1500cc derivatives. Weighing just 84kg, the shrill Hayabusa revs to 10,500rpm in first to fifth and 11,000rpm in top. It is rolling-road tuned to provide 180bhp at the wheels, the CSP1 category maximum for bike engines.
A 55kg weight saving over 200bhp Ford Zetec or Rover K series engined cars endows the PR24 – weighing in at 500kg, less driver – with 360bhp/ton performance and 145mph potential.
Transmission
Tim Gray Motorsport developed the longitudinally-mounted transmission
Photo by: Joy Batchelor
Mounted longitudinally, as opposed to transversely in motorcycle applications, the Suzuki Hayabusa engine is mated to its own compact six-speed gearbox, operated by a paddle-shift system – flat up, autoblip down – developed by the highly-rated Tim Gray Motorsport.
Two more cogs than conventional Clubmans ‘car’ boxes is advantageous, although overall gearing to suit different circuits is altered by changing between 3:3:1 and 3.1:1 ratio diffs. Drive is transmitted by a long shaft to the left of the cockpit, with stout impact protection for safety.
De Dion axle
The de Dion tube rear axle is a constant of Phantom cars
Photo by: Joy Batchelor
A constant of Phantom cars, the de Dion tube rear axle – a concept pioneered in the late 19th century – reduces unsprung weight and provides a stiff stable location for the independent driven wheels with zero camber change during cornering. Static camber adjustments are made via shims, to maximise tyre contact patches, and there is also toe control for alignment.
Laterally mounted centrally by a Watts linkage, with outboard radius arms, the robust tube is suspended by Spax dampers with bump and rebound valving within vertical coil springs. Front suspension is inboard, pushrod operated.
Wheels are 13-inch diameter, with 9.5 and 10.5 inch widths.
Phantom PR24 has already been a winner in Champkin’s hands
Photo by: Joy Batchelor
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