“It now has an over-bored 1398cc A-series,” he explains. “The engine is in a fairly gentle state of tune – it isn’t wild because I built the car for road use.
“It’s got 10.5:1 compression with a mild-to-warm road cam and a rally-spec head.
“A Nick Garrett exhaust at a stroke improved power and fuel consumption, and reduced noise dramatically, which goes some way to compensating for the induction noise from the Weber.
“If I was doing it again I’d build it with SUs.”
The Unipower GT’s low-slung cabin has the feel of a Ford GT40 in miniature
Despite various performance upgrades, including Cooper ‘S’ front discs like the original concept, the car clearly has a roadgoing focus.
“That’s why the wheelarches are the way they are; I wanted it to look broadly how it came out of the factory, which meant retaining the original body shape, meaning that it has to run 145-section tyres.”
Those narrow tyres might look a bit dainty, but they give the Unipower nimble handling that complements the chassis’ 48% front, 52% rear weight distribution.
Carpenter has spent a lot of time fettling the suspension geometry of his car, and the results are impressive, with a well-sprung and characterfully bouncy ride that is more reminiscent of that of the Mini than anything else here.
These neat vents extract hot air from the Unipower’s engine bay
Even the gearchange is sweet – a minor miracle, given the convoluted track the linkage follows from the driver’s-side sill to the gearbox.
It adds to the mini-GT40 feel, as if the Le Mans racer has been shrunk in the wash.
Stepping out of the Unipower GT leaves you wondering why this little mid-engined sports car didn’t run into the thousands rather than the 75 that eventually left the factory.
Though it clearly had the recipe for success, Powell lacked staying power and sold the company to young racer Piers Weld-Forester in 1968.
A reminder of where the Unipower’s engine is
The new owner started brightly, with a well-equipped workshop and a revised Mk2 version launched in ’69, but like so many before him he was lured on to the rocks in his pursuit of competition success.
He came close to realising his dream until a works-prepared car was crashed after-hours by a mechanic ahead of the Targa Florio, and a month later a 1340cc-engined car touched 140mph on the Mulsanne before blowing up in practice.
Ultimately, the project haemorrhaged money and the focus on racing forced the doors to close before the year was out.
The Jem has cheeky styling (left); the Deep Sanderson is a pure racing car
After a day of driving everything from highly tuned road cars to Le Mans warriors, I’m left wondering whether their commercial failures were down to the designs themselves or to the mismanagement, feuds and over-ambition that mark each story.
And to what extent Lawrence, Unger, Delmar-Morgan and Ogle realised the capability of the Mini, unlocking the potential inherent in the Issigonis wonder.
Ultimately, both the ambition and the ingenuity that led to the Deep Sanderson, Mini Jem, Unipower GT and Ogle SX1000 are reflected in their current owners.
All four brilliantly carry the spirit and traditions of their makers into the 21st century
Whether honed for racing or for the road, each of our test cars has been endlessly tinkered with, tuned and fettled.
Those original visionary designers and low-volume manufacturers saw something greater in the Mini; in turn, the true potential of their labours is still being realised more than half a century later.
Images: Luc Lacey
Thanks to TTP Performance (01527 882356)
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