Review: Mini R57.I Cabrio (2009-10)

Overview

Released in March 2009, the Mini R57 Series I (R57.II) Cabrio was a four-seat convertible with a power-operated, soft-top roof. Manufactured in Cowley, England, the front-wheel drive R57 Cabrio range consisted of Cooper, Cooper S and John Cooper Works variants.

Engines

Of the engines,

the Cooper variant had a naturally aspirated, 1.6-litre ‘Prince’ engine which had a cast aluminium cylinder block, double overhead camshafts, four valves per cylinder, variable intake valve lift (based on BMW’s ‘Valvetronic’) and a compression ratio of 11.0:1;
The Cooper S engine added a twin-scroll turbocharger (with boost pressure limited to 0.8 bar), common-rail direct injection, infinite intake camshaft adjustment, sodium-filled outlet valves (for greater cooling) and the compression ratio was lowered to 10.5:1; and,
The John Cooper Works engine increased boost pressure to 1.2 bar, had a stronger cylinder head and valves, a modified air intake, free-flowing exhaust and a compression ratio of 10.0:1.

Transmission options consisted of six-speed manual and automatic units (see table below).

Dimensions

Compared to the MINI R52 Cabrio , the R57 Cabrio was 64 mm longer (at 3699 mm), 5 mm narrower (1683 mm) and 1 mm lower (1414 mm), though wheelbase length (2467 mm) was unchanged. Although similarly styled to its predecessor, the R57 Cabrio was longer and had a pop-up rollbar which replaced the R52 Cabrio’s fixed hoops.

Suspension and steering

The Mini R57 Cabrio’s front suspension consisted of a single-joint MacPherson spring strut axle, while the rear Z-axle had longitudinal struts with centrally-pivoted control arms; the R57 Cabrio also had an electric power steering system.

Mini R57.I Cabrio specifications
Variant	Engine	Trans.	Peak power	Peak torque
Cooper	1.6-litre petrol I4	6sp man., 6sp auto	88 kW at 6000 rpm	160 Nm at 4250 rpm
Cooper S	1.6-litre turbo petrol I4	6sp man., 6sp auto	128 kW at 5500 rpm	240 Nm at 1600-5000 rpm
John Cooper Works	1.6-litre turbo petrol I4	6sp man.	155 kW at 6000 rpm	260 Nm at 1850-5600 rpm (280 Nm at 2000-5300 rpm with Overboost)

Safety equipment

Standard safety equipment for the Mini R57 Cabrio included dual front airbags, front seat-mounted side head/thorax airbags, ABS, electronic brake force distribution, brake assist, electronic stability control with cornering brake control, traction control, an automatically deploying roll bar and front seatbelts with pretensioners and load limiters.

Features: Cooper and Cooper S

Standard features for the Mini Cooper Cabrio included 15-inch alloy wheels, a six speaker sound system with CD player, MP3 compatibility and USB inputs, air conditioning, rear fog lights, cruise control, rear parking sensors, split and folding rear seats, a multi-function steering wheel, remote central locking, power windows and mirrors, ambient lighting, height adjustable front seats, tinted windows, a tilt and reach adjustable steering column, tyre pressure monitoring and an immobiliser.

The Cooper S was further equipped with 16-inch alloy wheels and contoured sports seats.

Mini John Cooper Works Cabrio

The John Cooper Works variant was differentiated by its 17-inch alloy wheels, climate control air conditioning, bi-xenon headlights and combination cloth/leather seats. The John Cooper Works variant was also fitted with four-piston front brake calipers and a front electronic differential lock which could brake a spinning wheel to transfer torque to the opposing front wheel.

Cooper Chilli and Cooper Chilli S

The Cooper and Cooper S were also available in Chilli editions. Compared to the Cooper Cabrio, the Chilli edition added a ten speaker sound system, front fog lights and contoured front sports seats with combination cloth/leather trim. The Cooper S Chilli was further differentiated by its 17-inch alloy wheels, climate control air conditioning and bi-xenon headlights.