Tuning test

Opel Manta 200i

When I first reported on the GTE version of General Motors’ venerable Manta, I felt that an essentially successful recipe was only spoiled by a relative lack of power. The last (and probably final) revisions to the old Ascona / Cavalier-based coupe and the replacement of the saloon by the front-wheel-drive model had at last given the Manta an identity of its own, and one which was developed through rally successes into an image of high-performance.

Yet, despite the sudden and even unexpected revitalisation of Manta sales, its increasing age and decreasing importance in relation to the Anton GTE have combined against it within GM, so that the company have not felt constrained to replace the rather pedestrian 2-litre 110 bhp block with anything more sporting. Enter the German tuning concern Irmscher, specialists in Opel preparation, with a choice of kits to make the GTE get up and go. Irmscher products are handled in this country by Steve Thompson Cars of Walsall in the West Midlands, who kindly loaned our test car.

Almost every Opel has been looked at by Irmscher, and kits available range from body parts for the Monza coupe, through tuning, handling and body kits for Ascona Cavalier, Manta, Astra / Kadett, and the baby of the range, the Nova or Corsa. Probably the most startling of these is the cabriolet conversion on the Nova. With its aggressively restyled nose and its fully disappearing hood under a GRP rear deck, the Nova Cabrio is a snappy looking vehicle, though its diminutive size has a touch of Toytown about it. Irmscher must have thought so too, for they also produce a kiddies’ version powered by a 100 cc petrol engine and costing £1,850.

Options for the Manta (and of course earlier Vauxhall versions) come in a wide variety, and for simplicity’s sake complete cars are offered in two forms, the i200 and 040 whose designations echo that of the limited production rally-winning Manta 400. Production of lrmscher’s version, though, is far from limited, with a claimed figure of well over 3,000 so far for the i200 alone. But fear not, those of you who dread anonymity; the sum of the body changes, small enough in themselves, is enough to puzzle many an onlooker as to the origins of this rapid-looking motor in its standard white livery. Irmscher count themselves as manufacturers, not converters, assembling complete cars from basic shells supplied from Opel at Russelsheim, and the cars arrive in Britain with body and all trim components in brilliant white.

When Motor Sport visited the Steve Thompson showrooms towards the end of last year, the specification and price for the British version of the faster i240 had not yet been settled, so we elected to stick with the slightly less powerful but appreciably cheaper i200. Whereas its big brother has upwards of 150 bhp, lowered and revised suspension and heavily flared wheel arches, and costs El 1,000-£13,000, the i200 retains the already excellent spring and damper settings of the GTE, and contents itself with a works 400-style boot spoiler and twin-headlamp conversion. The purposeful look that results is intensified by the addition (a no-cost option) of lower body stripes in the colours of Rothmans, although our demonstrator also had large decals advertising its origin, which I could have done without. White alloy wheels in the GM five-spoke style complete the outside, while inside is mostly standard, except for the large Opel badges adorning the Recant seats.

Both camshaft and distributor are replaced by Group A items, solid lifters are fitted, and a larger bore exhaust system helps boost power to 134 bhp. Our demonstrator was also fitted with a Group A cylinder head which pushed the output to just over 139 bhp. Torque is fractionally improved by 4 lb ft to 123.5, but the brochure continents puzzlingly that the peak torque shifts from 3,400 rpm to “a more usable 5,000 rpm”. Perhaps Irmscher’s engineers think in terms of competition engines, but such a torque curve is far from ideal for a road car, and this in fact proved to be the car’s weak point.

With its extra power, the Manta becomes very satisfying to drive at speeds where the standard engine would protest noisily, nosing between bends with its crisp exhaust note as if it were enjoying itself as much as the driver. It is surefooted and positive, evoking more and more confidence as successive bends are dismissed with a brief chirrup from the 195/60 Goodyear NCT tyres and a flick of the gear lever from third to fourth. Fifth is a comfortable cruising gear, with usable punch, but the penalty for all this high-speed willingness is the need for much gear changing at town speeds. It is not that the engine is particularly feeble at lower revs, merely that one must remember to drive it on the rev counter in order to take advantage of those small gaps in traffic when they suddenly appear. I found myself frequently using a gear lower than I would have expected for this reason.

Overall quite a relaxing vehicle to drive, the ;no has a few niggles for its driver, these being the preserve of Opel, not Irmscher, such as the high-set steering wheel, dated (but legible) fascia, and pedals which make it difficult to heel-and-toe. Opinion varied on the ride quality, some passengers finding it “jiggly”, but the driver looking for performance may expect or even welcome this as a sign of its ultimate capabilities. The seats offer good support, but do feel hard after a few hours. A decent-sized boot and reasonable rear seats make the Manta quite a practical coupe, while the action of the well-placed gear lever is easy, if a little notchy.

Too much right foot will spin the wheels very easily, and the best 0-60 mph times called for a steady throttle, when figures fell to about 7.7 sec. This compares well with the standard car’s 9.0 sec, but maximum speed seems little changed — over a two mile test straight, the 000 crept up to an indicated 127 mph on the over-reading speedo. If anything that is slightly down on the 120 mph for the plain GTE, though I cannot see this as of much relevance.

With the standard GTE Coupe costing £7,281, the total for the i200 when tested came to £8,446 — reasonable value for an attractive and eager sports coupe. But since then the price has risen to £8,666 (plus £175 for the Group A head) which begins to make the standard GTE look more of a bargain than ever. — G.C.