OPEL MONZA GSE REVIEW

A refined and brawny rear-drive coupé – what’s not to like?

The Monza was a part of the prestigious Opel Senator range from the car’s launch in 1978, and marketed as the luxury grand tourer of the line-up. Engines were almost exclusively six-cylinders, with early 2.0 and 2.5-litre mills soon supplanted by more powerful 2.8 and 3.0-litre engines.

Around 40,000 Monzas are thought to have rolled off the German production line, although relatively few survive today. With a powerful straight-six engine and excellent refinement, the GSE was capable of transporting four adults in long distance comfort, but could also play the role of performance hatch if the driver was in the mood.   

VITAL STATISTICS

1984 Opel Monza GSE 3.0

Engine                                    2968cc/6-cyl/OHV

Power (bhp@rpm)                  178bhp@5800rpm

Torque (lb ft@rpm)                 183lb ft@4200rpm

Top speed                                133mph

0-60mph                                  8.9sec

Consumption                            29mpg

Gearbox                                    4-speed automatic or 5-speed manual

WHAT TO LOOK FOR

BODYWORK & CHASSIS
 

With the last models now a quarter of a century old, it comes as no surprise that any used purchase needs to be checked carefully for rot. Pay particular attention to the the bottom of the A-pillar where it meets the inner wing, the rear wheelarches, around the sunroof aperture, and the rear of the sills where they meet the bottom of the wheelarch. The rear of the chassis as it passes over the rear axle is another weak point, as is the rear valance beneath the bumper. Take a good look under the bonnet as the top mountings for the suspension struts and the front chassis rail around the steering box are known rust spots, and the latter is a tricky and potentially costly repair. Watch too for signs of rust around the windscreen as water leaks here can cause electrical problems. Bear in mind that Monza-specific parts such as light units and body panels are getting rare now – owners clubs can help with tracking down replacements. Paint colours were limited but Carnelian Red and White are probably the most popular and combined with the lovely anthracite alloys suit the big coupé well.

ENGINE

The 2968cc straight-six engine with its ‘cam in head’ OHV layout was a strong and fairly simple unit and poses few problems if looked after. It was also relatively under-stressed and is easily capable of 130,000 miles before major work is necessary. Oil leaks tend to be limited to a failed cam cover gasket but what you do want to see is evidence of regular oil changes as these are key to preventing expensive failures of the timing chain tensioner and excessive valve-train wear. Leaks from ageing fuel injection system pipework can be common so a thorough check is needed here, while any signs of overheating should also be treated with caution as a high-mileage example could have succumbed to head gasket failure. While availability is limited, parts are relatively cheap so major engine work is well within scope of the home mechanic. 

RUNNING GEAR

Most GSEs were specified with the smooth-shifting 4-speed auto gearbox. These are largely trouble-free so it is just a case of checking for any jerky gearchanges. Rarer and more desirable is the 5-speed manual Getrag gearbox. These are robust units that should be slick in operation, and while specialists can rebuild them, it isn’t a cheap job. A mechanical limited slip differential was standard on the GSE so listen out for clunks or whines as a replacement is costly. The brakes were well up to the job, and while replacement brake parts are scarce, seized rear calipers are the only other issue to watch for. Rust can break through around the mountings for the rear trailing arms, and failure of the steering column’s tilt mechanism isn’t unheard of – the latter can be repaired though.

INTERIOR

 Opels of the period were renowned for their solid interior quality. The most striking part of the dash is the LCD instrument pack and this is generally reliable. The superb Recaro sports seats can wear on the bolsters, and there is a weak spot where the seat’s backrest pivots to let passengers into the rear which requires a strip-down of the seat to remedy. The only other issues of note are failure of the heater blower motor due to worn bearings, and failed electric windows.

OUR VERDICT

Anyone after a refined and well-equipped car capable of long-distance comfort should have the Monza GSE on their shopping list. Solid build quality and a decent turn of speed are pluses and careful checking will avoid the tired examples lurking on the used market. The GSE offers good value at the moment but prices are rising, so this is the time to buy.

CLASSIC CAR REVIEWS - OPEL MANTA

Looking for a stylish coupé but you don’t have much cash to spend? Then check out GM’s Opel Ascona-based Manta, which offers far more fun per pound than some more obvious alternatives...

There’s something that’s just so Seventies about a rear-wheel drive coupé. But while the obvious choice wears a blue oval, there’s a less predictable alternative and that’s the Opel Manta. First seen as the Manta A in 1970, this was followed up by the heavily revised Manta B in 1975, offered solely in coupé form alongside the identical Vauxhall Cavalier GLS coupé.

For 1978 there was an extra bodystyle for those seeking extra practicality – a hatchback, or as the Cavalier was known, a Sports Hatch. Both the Opel and Vauxhall were sold alongside each other with a choice of bodystyles until the Cavalier was dropped in 1981. Not only did the Opel continue, but it was refreshed in 1982 to become the Manta C in the UK (the Europeans retained the Manta B tag), and it would remain in production until 1988.

Along the way the Manta was offered with a choice of engines, most based on the same cam-in-head design. At first there was a 1.6-litre unit which was soon killed off, while for Europe there was a 1.2-litre option. UK buyers got a 1.9-litre powerplant until 1978, when a 2.0-litre lump took over. From 1982 there was also a 1.8-litre overhead cam option, but few of these are left, so you’ll be doing well to find one.

While pre-1982 cars are desirable because they’re rare and feature a relatively pure design, it’s the later fuel-injected GT/E that’s the most sought after Manta, along with the GT/E Exclusive (later just Exclusive) that arrived in 1986. As the last of the line these models are the fastest of the breed but also the ones most likely to be suffering from really bad rot. While major corrosion is a common issue, the Manta is enormous fun, a little bit left-field and eminently affordable. Which begs the obvious question: what’s not to love?

WHAT TO LOOK FOR

Bodywork

Rot can set in pretty much anywhere, but key areas to examine include the panel area above the headlights (especially if cheap aftermarket quad-headlamps have been poorly fitted), the rear arches (they seem to suffer more than the front arches) and the sunroof aperture – as well as the sunroof panel itself.

Rotten doors are often evidence of cheap pattern parts, since the factory doors seem resilient to corrosion. The three-door’s tailgate is prone to corrosion around the base of the window, while the coupé’s boot floor is a known weak point.

Inside, lift the carpets and check for rot in the floor – water gets in via the side windows. Check underneath, too the hatchback’s petrol tank is vulnerable to rust, as it’s positioned under the floor; it lives behind the rear seat on the coupé.

Engine

Mantas are powered by a four-cylinder ‘Cam-in-Head or CiH engine. High performance models were produced (Irmscher i200/i240, Manta 400), but in relatively small numbers. B2 cars are either 1.8 OHC or 2.0-litre injection CiH units.

Each is strong and capable of six-figure mileages before re-builds, with evidence of blown head gaskets and oil leaks the only real areas of concern. If the head has been removed at some point, make sure it was replaced by a knowledgeable specialist – the correct re-torquing of the bolts is absolutely critical to the engine’s longevity. Ask to see evidence of a correct cambelt change, too – this job should be done every 30,000 miles on the 1.8.

Don’t be too put off by some engine noise the chain-driven camshaft chatters at idle even on healthy engines; and (short-lived) rattling from the hydraulic tappets is normal.

Running gear

Beware any car that whines persistently or baulks at changes – especially into second or third gear. The five-speed Getrag gearbox fitted to all post-1982 UK Mantas is a tough unit that should pretty much outlive the car.

Elsewhere, issues to look out for include noisy rear axles (replacement is usually the only solution) and excessive drivetrain judder, which is curable by replacing the universal joints on the propshaft; it’s rare for the propshaft itself to give up the ghost.

Soggy handling can often be traced back to worn or broken springs/dampers, while shrieking brakes, a rock-hard pedal and poor retardation all point to seized callipers. A brake pedal with little or no feel is probably down to a failed brake master cylinder.

Interior

Avoid cars with shabby interiors, unless you have new trim on standby, as hardly any interior trim is available nowadays. The Manta’s interior is of a high quality and hard-wearing, so only badly treated cars should pose a problem. Hard or damaged window and door rubbers will wreak havoc on the carpets and floorpan, however.

The Manta’s electrics are straightforward as they’re so simple; there were no powered windows or air-con to worry about. If the gauge readings are way out it’s because the voltage stabiliser has failed; new solid state replacements cost £12 apiece and they’re easy to fit. More of a problem is damaged trim, because while everything is hard-wearing, finding used parts is a nightmare. The same goes for the exterior trim; there isn’t much of it, but if anything is missing, you’ll be doing well to find anything you might need.

OUR VERDICT

More than 550,000 Mantas were made between 1975 and 1988, but the survival rate is poor. If you want a good one you’ll have to search hard – especially if you want one that hasn’t been modified. But the good news is that if you do find one, you won’t have to dig too deep to buy it.

OPEL GT COUPE REVIEW

Previewed in 1968, and really made for mainland Europe, the rare two-seater Open GT was only available in LHD form in the U.K., but what a pretty little car! General Motors' Opel GT was the only true sports car that Opel produced. Visually a mini Chevrolet Corvette - also from GM - the GT used the same platform and suspension as the Kadett, and while there was a choice of engines in Europe, only the 90bhp 1,897cc Rekord unit was available in the U.K. Although rare here and rather expensive at £1,882 against a Triumph GT6 of the period at just £1,287, total production of the Opel GT ran to just over 103,000 - enough for spares not to be too much of a problem. Performance was brisk, returning a top speed of 115mph.

OPEL ASCONA REVIEW

Produced in three generations from 1970 to 1988, the Opel Ascona started out as a rear-wheel drive but ended up as a front-wheel drive J-body derivative.

Launched on 28 October 1970 as a competitor to the successful Ford Taunus (Cortina), the Ascona was available in two and four-door sedan form with petrol engines from 1.2L to 1.9L. Sold at a premium price alongside its counterpart, the Vauxhall Cavalier, the Ascona A remained in production until 1975, in which time almost 692,000 vehicles had been produced.

The Ascona B was presented in August 1975 at the Frankfurt Motor Show. It retained the same engine range as the first generation Ascona but, unlike the Ascona A, the B was only available as a saloon, not an estate.  In 1978, the 1.9-litre version was replaced by a 2.0-litre 100bhp version, capable of a 110mph maximum speed and 0-60mph time of 10.0 seconds.

Branching out into Group 4 racing, the Ascona 400 was officially born on 6th March, 1978. The homolagation regulations required the production of four hundred cars to be able to compete in Group 4. The Ascona 400 was derived from a 2-door Ascona B, but a number of aerodynamic features changed its appearance. There were large front and rear spoilers, skirts beneath the sills and widened front wings, but it was not only in cosmetic looks that the competition car differed from its production brother.  The engine ran on 48 DCOE Weber carburettors achieving 240 bhp at 7,500 rpm with peak torque a staggering 2001b ft at 5,000 rpm.

Production of the Ascona B finished in August 1981, when the third and final generation of Ascona saloon was launched, although the front-wheel drive Ascona C wasn’t sold in the UK. Production of the Ascona ended in 1988.