Initially predicted as General Motors’ answer to rallying homologation weapons such as the Toyota Celica GT4, the turbocharged, 4×4 Vauxhall Calibra trim has transpired to be more important as a showroom item than a World Championship contender.
Priced at £20,950 to head a Calibra line that is otherwise now composed of normally-aspirated eight-and 16-valve four cylinders, there are no concessions outside the engine bay to assist its progress at world class rallying levels. Instead, Vauxhall bills the 204 bhp Calibra as ‘The Ultimate Coupe’ and promotes standard items such as the first production transverse six-speed gearbox, a claimed 152 mph, 0-60 mph in 6.4 sec and leather clad seating.
The philosophy has been very much that of altering as little as possible in the transformation of a 150 bhp 16v 4×4 Calibra (no longer listed) into a turbocharged big brother with a power bonus of 36 per cent and a massive 42 per cent hike in maximum torque. Thus the 204bhp at 5600 rpm and 206.5 lb ft of torque at just 2400 are complimented by few changes in running gear, items such as suspension, steering and body panels having been left untouched.
This has the advantage of preserving a drag factor officially asserted to be 0.29Cd, but when Vauxhall or Opel decides to use it in national competitions – rallying in the UK, racing in Germany – the lack of extra cooling slots and a compact intercooler installation are likely to be greeted with engineering expletives.
The replacement Getrag gearbox sextet (currently exclusive to GM) and bigger (ex-Opel Senator) disc brakes lie behind unique alloy 6Jx 16 wheels. Other changes were budgeted out of the question, but standard equipment is generous for the customer, embracing a useful computer (we recorded 24.1-24.8 mpg), Bosch ABS and electric operation of the ‘up and over’ sunroof, side glass and mirrors. Vauxhall takes anti-theft a lot more seriously than Ford and provides effective deadlocks and an ultrasonic alarm.
(Created by a small cell of engineers working within an advanced engineering group inside Russelsheim HQ, the turbocharged 1968 cc (86x86mm) motor is billed as having an “integrated, no lag” turbocharger. The KKK-KI6 unit is unusual in that the turbine housing and exhaust manifold are one, saving the need for a connecting flange and potentially troublesome gaskets. GM prefers to highlight the weight reduction achieved, and advanced product engineer Ingo Janthur confirmed that the saving of 11 lb had been put to good use in offsetting any undue nose weight generated by the six-speed gearbox (to be confined to the Calibra, for the foreseeable future) and the addition of a turbo.
The motor remains – essentially – the much-praised 16v, dohc, design. Compression is lowered to 9:1, a special gasket is fitted and there were minor lubrication changes to service the turbocharger. However, the gearbox casing is all-new and the overdriven 0.74 ratio picked for sixth gear is meant to achieve top speed, 152 mph representing 6003 of the 6900rpm allowed for continuous operation on the 8000 rpm tachometer.
Aside from the black leather trim, the cockpit feels the same as any other Calibra, but your driving impressions are dominated by the turbocharged engine. The positive aspect is the immediate delivery of pulling power. I am sure that, technically, lag-free turbo operation is not possible, but the response is the fastest I have come across in a turbo motor and very commendable. Higher up the rpm scale there were resonances from 4500-4700 rpm that I had not noticed in the normally aspirated 16v Calibra 4×4 that Motor Sport tested in 1991, but sixth gear avoids the need to travel in these rpm zones, unless you are determined to sustain 113-119 mph. At 100 mph/4000 rpm you simply bless the Calibra’s clean shape as it hisses through the air with unrivalled ease.
Pick up from less than 2000 rpm in sixth gear is impressive and the adequate change quality is similar to that of a conventional five-speed Calibra or Cavalier, sharing most of the shift linkage. Whilst the main road manners of the Calibra set new mass production standards for motorway speed and stability in balmy Mediterranean conditions, its B-road abilities are still below those of a Lancia Delta integrale or Ford 4×4. The rack and pinion power steering is accurate, numb and becomes uneasy as power is applied from slow hairpin bends, especially uphill. The damper settings are those of the 16v Calibra (but not the equivalent Cavalier GSi) and the ride over poor surfaces reflects the fact that such roads are not a priority to German engineers.
This Calibra is prone to choppiness over bumps and is influenced by cambers in a manner that even the oldest Audi quattro eschewed 12 years ago. We thought the latest Calibra an honestly priced machine that will reach a disappointing number of customers in Britain.
Vauxhall sales director Peter Batchelor anticipates that just 500 of 6500 Calibras sold in 1992 Britain will be of the turbo 4×4 breed. For all the motoring press hullabaloo over the rebirth of the coupe market in Britain, sales numbers of such speciality cars remain low in the ’90s. At plants in Finland and Germany, GM expects to make about 60,000 Calibras in 1992: in 1973, Ford was making over 233,000 Capris per annum….