Coupé Climax

Introduced to Britain in June 1990 as the Vauxhall Calibra (the LHD variant simply wears an Opel prefix), this sleek coupe on a Cavalier base has restored European pride in its market sector. Previously, if you wanted to buy an affordable two-plus-two, it was either an aged VW Scirocco, the excellent but unfashionable Corrado, or a Japanese offering.

Initially only available as a front-drive or normally aspirated (150 bhp) 4×4, the Calibra has now evolved to offer the cheapest 150 mph mass-production parcel in Britain at £20,950. Low drag aerodynamics (still under the 0.30 Cd barrier) help it achieve a respectable 23.6 overall mpg. A 0-60 mph time in the six-second bracket reflects that the 204 bhp provided has to work against a kerb weight in excess of 3000lb. The extra 54 bhp is provided by a turbocharger installation, and it is this turbo variant that we test this month, complete with six-speed gearbox as standard, together with leather upholstery and uprated brakes.

There are snags — particularly in the wooden ride, inert handling and steering — but this turbocharged Vauxhall is still outstanding value. The Calibra has led something of a European revival in the British coupe market, but it remains a very small sector. The independent analyst Automotive Industry Data (AID of Lichfield, Staffs) tells me that a total of 27,795 coupes were sold in Britain in 1991, which represents just 1.75 per cent of all new car sales in a depressed market.

Other sources report that, last year, Vauxhall sold 5471 Calibras, decisively beating the assorted bunch which officials categorise as coupes. Toyota was second with 4053 registrations of the mid-engined MR2 which MOTOR SPORT tested last year, whilst the same company’s Celica was third with 2738 sales. The Volvo 480 is categorised here as fourth, whilst other top 10 runners included Nissan’s 200SX, Volkswagen with Corrado and Scirocco, Honda Prelude, and the Audi Coupe (all models). A fine part-year performance from Mazda brought the MX-3 into 10th.

This year, the first five months of coupe sales in Britain show much the same pattern as 1991 totals, the Calibra leading the Toyota MR2 handsomely. However, Honda’s Prelude (befitting from a new model which we recently enjoyed in the rain at Goodwood) has four-wheel-steered into third overall, and the Mazda MX-3 is now selling strongly enough to secure eighth position.

Vauxhall plans to sell only 500 of the Finnish-built turbo Calibras in Britain this year. Should you buy one instead of the rival Ford Sierra / Escort Cosworth RS opposition? We found out with experience in Britain and France of four similarly-specified RHD examples, one of which successfully survived a foray to the Polish Rally.

UK Range

Just over two years ago the launch prices of Calibras spread from £14,750 to £18,950. Today the range has been slightly simplified to feature a trio of Calibras from £15,577 for the eight-valve, front-drive ‘entry’ model — still capable of more than 125 mph — to the near £21,000 of the test turbo 4×4. A wealth of standard equipment is designed to cut out the need for options on this Calibra flagship: leather trim, metallic paint, alloy wheels, six-speaker stereo (from Philips), electric operation of door locking (supported by dead locks and an ultrasonic alarm), central locking, front side glass and a tilt or slide sunroof are all on the “No Cost Option” (NCO) or showroom specification. There is much more on those lists, but just take it as read that the Calibra Turbo 4×4 is exceptionally well equipped with toys to complement the hardware.

The mid-range Calibra is now delivered as a 16v/150 bhp front-drive variant (formerly also available in 4×4 and tested by MOTOR SPORT). That FWD package, which combines nearly 140 mph with 25 mpg economy, is more strongly flawed by its handling traits, but remains testimony to the efficiency as well as the style of that elegant body, labelled by one of our monthly contemporaries as “one of the finest looking cars in the World, regardless of price”.

Technical analysis

Adam Opel has seen that small groups of engineers charged with specific tasks bring results, and can become commercially useful in establishing credibility. Thus a small Advanced Product Study Group was formed within the main Russelsheim engineering department to work in close co-operation with their resident engines engineering expert, Dr Fritz lndra. The Good Doctor Fritz has done it all in the performance business. He spent a youthful spell on Niki Lauda’s Formula Vee racers, graduating to engineering at Alpina-BMW (concentrating particularly on their turbocharged layouts on the big sixes of the early Eighties) and a very senior engineering position at Audi in Ingolstadt. There he was responsible for much of the four-valve per cylinder engineering of the period, especially the abbreviated 300 bhp quattro Sport.

For the Calibra turbo project, the engineers were told only to complete the quick response turbo installation, co-operate with Getrag on the construction of the exclusive six-speed gearbox (a first for a transverse-engined production car), and uprate the front brakes with their ABS system. Ingo Janthur, a staff project engineer within that grouping, told us, “we did not have money or instructions to do more than this. There was absolutely no plan to make a World Rally Championship car, or anything like this. We would not have left the body panels entirely alone, or used the unique KKK-K16 turbocharger with a small intercooler, if we wanted to win in motorsports”.

Thus the basis of the factory conversion was the 16-valve 4×4, which was asked to yield 36 per cent more power — up from 150 to 204 bhp — than the already effective 16-valve unit. Even if the resulting figure of 102.8 bhp per litre does not seem unduly impressive by today’s standards, the engine’s extremely flexible pulling power is. The torque reaches 206.4 lb ft at a low 2400 rpm, but, more important than that, almost 150 of those pound-feet are on tap between 1500 and 4200 rpm.

Items such as the power steering and chassis — right down to the spring rates — were left as for the 150 bhp Calibras. What makes the car feel a lot stiffer than before is the use of 16-inch diameter wheels and 50 per cent low profile tyres. The only significant chassis change was an increase of 28mm in front brake disc diameter. Mechanically the 16v engine is also little changed in basics: major reciprocating components remain as before, including a cast-iron crankshaft. The lighter pistons now run a 9: 1 cr instead of the normally aspirated ratio of 10.5: 1 , thanks to small indents in the piston crowns. The aluminium crossflow cylinder head design remains as before, served by Bosch 2.7 Motronic management. However, the head gasket is replaced with a reinforced item that features “stainless steel edging and webbed plate”. Sounds fit for the kitchen, does it not?

The unit exhales via twin tail pipes in an oval casing, its breath cleansed by a catalytic convertor. The engine was designed to operate on 95 octane unleaded, rather than the more expensive grades specified for so many other West German performers, and it proved exceptionally economical on test, in line with Vauxhall claims that “the Calibra Turbo needs only 0.2 litres per 100 km (62 miles) than the naturally aspirated version.

The KKK turbo casing is unique in that it is integrated with the exhaust manifold, reducing weight over the front axle and eliminating a bolted junction which can be a pest in service. No maximum boost figure was vouchsafed. The gearset, featuring two overdriven upper ratios, allows excellent progression through the ratios and a relaxed 25.32 mph per 1000 rpm in sixth. However, GM did not take full advantage of the chance to choose theoretically improved ratios. Second gear releases slightly less than 60 mph at nearly 7000 rpm so that 0-60 mph times do not quite match the engine’s potential, requiring an extra gear shift when compared to most obvious opposition.

The gearchange gate is exactly as for a manual five-speed Vauxhall, plus a slot for sixth 2 closest to the RHD operator. The casing is dimensionally similar to that of a five-speed and no alterations are made to install the six-speed. 4) That means the Cavalier, or other Calibras, could benefit from the new sextet, once the shine has faded from the Calibra Turbo’s debut — but Opel engineers deny any plans for six-speed saloons. The 4×4 element to the transmission is the same as for previous Cavaliers and Calibras, the system disconnected automatically when the standard ABS braking is activated. The propshafts, viscous coupling mounts and clutch pressure plate were reinforced to meet the 42 per cent increase in maximum torque.

Action

Vauxhall was unfortunate that our test Calibra coincided with our tenure of a BMW 318is coupe demonstrator. Although the cabin of the £17,000 BMW has attracted adverse comment in the four-door 3-series, it is still superior in tactile feel, ergonomic operation and discernible quality to anything that even a conscientious mass manufacturer like GM is currently providing in its coupes. GM-Vauxhall do try. The leather clad cabin looks very plush in pictures and we managed to carry a six-footer in the back without complaint. Closer inspection shows uninspired mixtures of black plastics, but excellent assembly standards.

When you come to operate the car regularly, detail niggles come to light: the multifunction computer is confusing with its central button operation (often mistaken for a central locking over-ride) and the instrumentation lacks even a boost gauge to boast its new status. However, the dials are clearly laid out and the quickly adjustable steering column made a wide variety of testers welcome with a carefully shaped leather-rimmed steering wheel. Vision for the driver is better than usual in this class with extended threequarter glass, although reversing is more of a problem.

Despite the low look, the Calibra does not feel claustrophobic for any of the occupants. It truly has all the practicality of a saloon and a measure of the exclusive excitement generated by some coupes. That remark seems churlish when you examine the performance figures, which were delivered easily. The maximum speed runs highlighted the lowest cabin noise levels we can remember at an honest 150 mph. The maximum measured was just over 151 mph, but the everyday bonus of this unusually clean shape is that motorway miles are unusually restful, helped by comparatively close ratios for the first five gears and a relaxed overdriven sixth ratio giving 70 mph for just over 2700 rpm. Even 100 mph does not unduly stress the occupants, requiring less than 4000 revs.

The gear shift quality is exactly like that of the normal Vauxhall five-speed, competent but no standard bearer, until you change from fifth to sixth. Usually the swop will be cleanly executed, but on occasion it will hang between fifth and sixth, as though it were uncertain which ratio was ordered. A major irony though, as with the BMW 850i, Porsche 968 and other six-speeders, is that the engine is so flexible that it really does not need all those ratios. We will applaud the day that Honda fits such gear clusters to the V-TEC Civics, or Rover to the 216 GTi, where they are needed.

The GM four does have a resonance period between 4500-4700 rpm that is better boycotted, and which we do not recall on the normally aspirated model. Thereafter, the 16-valve turbocharged four cylinder rips enthusiastically to a 6900 rpm redline. Mid range performance is also impressive, and Vauxhall are close to the truth when they promise a “no lag” turbocharging installation. The unit with its compact KKK turbo is biased toward providing the kind of instant overtaking performance you would expect of a three-litre six. A very successful road installation, but one without the high rpm competition potential that might have been expected in some quarters.

On better tarmac surfaces, at home or abroad, the ride is acceptable, though not as good as one might have been expected from a wheelbase of almost 103 inches. Anything like a British B-road surface turns the cabin into a punishment cell. Not because it is particularly harshly damped, but because it is so restless, jiggling over most common bump sequences and downright headstrong if the overall road camber is against you as well. Similarly the cornering capabilities seem fine on first acquaintance. The move to 16-inch wheels and a convincing supply of rubber from Firestone gives generous grip. The surprises came when we pushed a little harder. Even on public roads there was quite a bit of steering wheel shudder and the transmission appeared to be joining in. The multiple clutches and viscous coupling seemed uncertain which end to feed power to as the tyres skimmed over tarmac at high speeds on comparatively smooth surfaces.

o ensure that we were not imagining things, the Calibra was taken back to its spiritual test track home at Millbrook and put over one of their handling courses by three drivers — two staff men and a very well-known guest, whose Vauxhall links prohibit our using his name. We also had a high performance front-drive hatchback present to act as a benchmark. The sad fact was that the 4×4 turbo wonder could not keep up with its front-drive adversary over a course that emphasises 40-80 mph handling traits. It caught up slightly over a quarter mile straight, but otherwise, guest or staff driver, the Calibra could not actually put all that high tech to good use. This was simply because the wheels spent too much time pattering and juddering under power (as if it was the front drive model), whilst the steering punished palms, but (like legendary wartime heroes) “told them nothing”. Overall, we were impressed by the straight line performance, unimpressed by the Calibra’s chassis under cornering duress.

Verdict

The Calibra should be an irrestible buy for technocrats, those who like all the latest fashions in one package at an affordable price. Unfortunately nobody seems to have given enough thought as to how the “oily bits” all co-operate, and the result is a disjointed performer. Yet it is close enough that it could be much improved by the aftermarket specialists at low cost.

In fact the Calibra chassis is “a gift for the goodie men”, in the words of one tester. Though we do not see many Ford Cosworth RS owners defecting to the GM camp, we do see the Calibra wearing a technical crown in the fashion conscious coupe classes — glitter that will earn it, and the range beneath, further commercial success. J W