Opel Commodore 2.5S Berlina               Rekord promotion

IT WAS back in the summer of 1977 that the Opel Commodore disappeared from the motoring scene in Britain, and more than a year passed before the range was topped off with the arrival of the Senator and Monza. Now the Commodore has returned, to fill the gap between the Rekord and the top of the range cars.

   Like the previous model, the new Commodore shares the Re-kord's bodyshell, with a larger engine and uprated trim. The six-cylinder engine has bore and stroke dimensions of 87.0 x 69.8mm, which gives a capacity of 2,490 c.c. The now-usual Opel valve gear is used, with the chain-driven camshaft located in the cylinder head operating the valves through rockers, with hy-draulic tappets. A single twinchoke Zenith 35/40 INAT carburettor is fitted, and with a compression ratio of 9.2 to 1, the power output is a rather modest 115 bhp at 5,200 rpm. Maximum torque, at 125 lb.ft., is developed at 3,800 rpm. 

   With fuel economy in mind, Opel offer the Commodore with overdrive, although the test car did not have it. The standard four-speed transmission runs with a

3.45 to 1 final drive ratio, which gives 20.9 mph/1,000rpm. With overdrive, the final drive ratio is lowered to 3.7 to 1, which gives 19.4 mph/1,000 rpm in direct top and 25.1 in overdrive top. When the automatic transmission is specified, this comes with the same final drive ratio as the four-speed gearbox

  The suspension follows con-ventional lines, with MacPherson struts at the front and a live axle located by four links and a Pan-hard rod at the rear. Power steering, with recirculating ball gear, is standard on the Commodore, while braking is looked after by 10.67in. discs at the front and 9.06in. drums at the rear.

   The test car was an early non-standard model in terms of trim. 

Among the extras fitted were a steel sunroof, rear seat belts, central locking, electric window lifts, metallic paintwork and the front fog lamps. Many of these are standard on the top CD version of the Commodore.

Performance

More stately than dramatic

   The Commodore weighs some 3.9cwt more than the Rekord which we tested on 4 February 1978, but it has only 15bhp more to help it along. As a result, the performance tends not to be outstanding. The lower gear ratios are well chosen, with maximum at the rev counter red line of 6,500 rpm giving 37mph 

in first, 64 in second and 101 in third. At very high crank-shaft speeds the engine tends to feel and sound rather rough and noisy. As a result one tends to make full use of the more than ample torque. The gearchange has a smooth but rather heavy action, which does not encourage fast shifts. The well-located rear axle and the fat 195/70HR14in. Michelin XVS tyres mean that 

Despite its length, there is plenty of room to work round the six cylinder engine. The dipstick is alongside the distributor, with the washer reservoir and radiator header tank alongside. The bonnet is not self-supporting

the overdrive version. The 14.3 gallon fuel tank tends to be very slow to brim completely, and would give a range of around 270 miles with a gallon or so in reserve.

Road behaviour

No fuss, no bother

   In many ways, the Commodore is the very model of the family car, a solid, four-square vehicle without any pretentious frills. This also sums up the car's handling, which displays no vices and in normal conditions, huge reserves of grip.

  Power steering comes as standard on the range, and is well matched to the recirculating 

ball system. This may lack the ultimate crispness of rack and pinion steering, but the feel is good, and the degree of assistance just right. The big, fat Michelin tyres give superb grip, even in pouring wet conditions. When pushed into a bend too fast, the front tyres will let go first, but the car feels and stays in balance, so that it can be collected easily. The degree of understeer is what most drivers like, giving the car a stable, solid feel.

  The ride quality is excellent, especially on smooth main roads. The only time the Commodore tends to get caught out is when there is a pothole or man-hole right on the apex of a corner, which can make the rear axle skip a little, throwing the car off line.

Brakes

ample reserves

   To cope with the extra speed and weight the Commodore's front disc brakes over 1in. larger in diameter than those on the Rekord, while the rear drums are the same size. Initially they tend to feel a little on the oversensitive side, with just 20lb pedal pressure giving 0.5g. In practice, however, progression is very good, with 40lb pressure giving the best stopping of 0.98g, with the front wheels tending to lock up first. The Commodore came out of the tough fade tests with flying colours, with pressures rising from the initial 20/25lb up to a maximum of 40/50lb before 

Instrument panel layout in the Commodore is similar to that in the Senator and Monza, with large speedometer and rev counter clearly in view through the top half of the steering wheel, and flanked by voltmeter and coolant temperature gauge on the left, and oil pressure and fuel gauges on the right. Between the two main dials are warning telltales for headlamps main beam, indicators, oil pressure, charge, brakes and hazard warning, and trailer indicator repeater. Switches for the heated rear window, front (optional) and rear fog lamps, and two spares are fitted in the centre above the cool air outlets, and there is a quartz clock

Front seats are firmly comfortable. The driving seat can be height adjusted by the telescopic lever, and the head restraints are adjustable, Rear seat passengers have plenty of room to spread themselves, and the centre armrest adds to the comfort. There are ashtrays on the forward part of the doorpulls. The rear seat belts are an extra on the Berlina, standard on the CD.

rature and fan speeds; the fan is rather noticeable when on the higher settings. In the centre there are separate controls for air flow direction. For side window demisting, there are facia end vents, in two parts, so that the air flow can be directed on to the face or body as needed. Lastly a pair of vents in the centre of the facia admit unheated air, and the flow can be fan boosted. The test car had a slide and tilt manually operated steel sunroof. Controls for the electric windows are alongside the handbrake, on the extension of the centre console; a cut out switch on the facia prevents children from working the rear window lifts. There is also a pop-out overload switch protecting the motor circuits.

Living with the

Opel Commodore

One would expect a car in the Commodore class to have plenty of room in it, and it lives up to its image. Those in the rear have a generous amount of leg and headroom, and there is a fold-up armrest to improve location. Naturally the rear doors have childproof locks. The test car was fitted with electric central locking which covered the boot as well. A further refinement is an electric boot release, which operates only with the ignition on. The boot is fairly large, with a rather high sill. The spare wheel and jack are stowed out of the way in the lefthand wing recess.

  Inside the car there is a reasonable amount of room for stowing odds and ends. The locking glove locker has a shelf above it. Deep pockets in the front doors are useful for maps. On the centre console, what would be a useful tray for cigarettes or sun glasses was filled by a rather flimsy cassette rack; unfortunately the car had no radio/cassette player.

The six-cylinder engine fits neatly under the bonnet, with a short cowl shielding the fan. Access is generally fine, with the distributor and plugs on the right, with the dipstick easily reached. The power steering pump is on the left. The radiator has a separate transluscent header tank alongside the screen and headlamp washer reservoir.

The Opel is the "baby” of the six, with the smallest capacity engine and by far the lowest power output. The five other cars all develop well over 130bhp, which leaves the Opel's 115 bhp rather in the shade. All the engines have six cylinders: those in the Opel, Rover and Toyota are in line, the remainder are V6s, with those from the Peugeot and Volvo being the "co-op” one which is also used by Renault.
   The long-legged Rover, with its five speed gearbox, is the fastest of the bunch, with a top speed of 117 mph. The Opel with overdrive should be faster than the non-OD version, which is simply running out of revs at the 109 mean maximum.
   Off the line, the Peugeot has the legs on everyone, with the Granada not too far behind. The Opel's power-to-weight ratio does tend to chop down the acceleration.
   No doubt the Commodore's fuel consumption would be considerably improved with overdrive. One only has to see just how effective this is on the Toyota, which has the clever overdrive Aisin-Warner automatic transmission. Now that the Rover 2600 has an even higher fifth gear ratio, its fuel consumption should become even better.
   It is also likely that the Volvo 264 would make a better showing for performance in its new form, with 2.8-litre V6 engine instead of the former 2.6, but it is too early for us to have had a chance to test it with the new engine.
   In general assessment of the performance and economy offered by the cars in this group, it is all too apparent that the Commodore has a "soft” engine with the emphasis on refinement and good torque rather than sheer efficiency.

ON THE ROAD

MPH & MPG

Maximum speed (mph)

Rover 2600                 117
Peugeot 604                113
Toyota Crown (A)        113
Ford Granada             111
Opel Commodore        109
Volvo 264 GLE            100

Acceleration 0-60 (sec)

Peugeot 604                9.4
Ford Granada             9.9
Toyota Crown (A)      10.4
Rover 2600               10.7
Opel Commodore      12.2
Volvo 264 GLE          13.5

Overall mpg

Toyota Crown (A)       24.8
Ford Granada             24.5
Rover 2600                 22.4
Opel Commodore        20.2
Peugeot 604               19.6
Volvo 264 GLE           19.6

The handling of the Opel proves just how good a properly located live rear axle can be, and this is backed up by the way both the Rover and the Volvo behave. The Toyota Crown's rather poor rough road ride lets it down.

  Only the Ford and Peugeot have independent rear suspension. Power steering is available on all the cars. It is a mark of the progress over the past few years in that unless you were told, you would probably not realise that PAS was fitted. It is particularly good on the Commodore.