BMW's 735iA

More refinement, but is it yet a Mercedes beater? 

There was a time, about ten years ago, when the aspiring business executive might content himself with his Ford Granada, secure in the knowledge that one day he would graduate through the ranks of the BMWs eventually to arrive in a Mercedes-Benz. That was the order of things at that time, and very reasonable it all seemed to be. Opel hadn’t quite got their act together at the luxury end of the market and Jaguar customers were still something of a breed apart, many people still identifying long-term quality and durability strongly with the two aforementioned German marques.

Times change, and the crazy logic of inflation has made luxury car prices rocket to what might seem ridiculously dizzy heights, although this very fact has made the most expensive sector of the executive saloon market just as cost-conscious and competitive, in a relative sense, as the opposite end of the buyer’s scale. There are now more good, closely-matched luxury saloon cars on the market, not one of which can be branded as deficient in any significant sense, let alone bad. Yet cars still come the way of Motor Sport which we find difficult to assess in relation to their rivals: one such has been BMW’s revised 735iA saloon which we recently enjoyed for a week’s winter motoring.

I have to confess that the 735iA didn’t have a fair start: I climbed straight into its driving seat a few minutes after relinquishing custody of last month’s Ferrari 308GTBi to its owners, Maranello Concessionaires. Coming from the cockpit of an essentially responsive, out-and-out sports car into the “gentleman’s club” atmosphere of muted luxury offered by the BMW was a major culture shock. It took me several miles before I was sure that I could face manoeuvring a large saloon car again in heavy traffic!

BMW’s range of 7-series saloons burst onto the market at the end of 1977, some time after the 6-series coupés supplanted the old 3-litre CSLs. I think it is fair to say that they got a mixed reception: there were accusations that they had a somewhat “coarse” ride and didn’t provide the adhesion offered by some of their rivals. Neither did they receive unanimous acclaim on the basis of their looks. Some people considered them to be dumpy and badly proportioned when compared with the sleek, graceful lines of the big BMW saloon range which they replaced. But most people would agree that the cars’ specification has progressively improved and the well-equipped 1983 model, with its 3.5-litre fuel-injected engine, is undoubtedly the best yet. But the price for all its undeniable technical improvement has been a gradual movement of its price up towards the Mercedes-Benz bracket. Thus, while Stuttgart has successfully moved down-market to challenge BMW with its W123 derivatives, Munich has gradually moved up-market in an attempt to tackle Mercedes’s prestigious ‘S’ class saloons on their own ground. And spearheading Munich’s attack is the current 735iA.

Our test car was fitted with the optional automatic transmission system which is in effect a three speed automatic with an “overdrive” fourth which is only engaged on relatively modest acceleration. A clutch locks out this very high fourth on full throttle at anything above approximately 55 m.p.h. and, although it will engage at much lower speeds with a gentle application of the throttle pedal, continuous full-throttle running ensures that the 735iA stays in third gear all the way up to its maximum of around 130 m.p.h., this corresponding to 5,750 r.p.m. The revised 735i employs the slightly smaller 3,420 c.c. six-cylinder o.h.c. engine which first appeared installed in the current 635CSi, developing 218 b.h.p. at 5,200 r.p.m. with a 10.0:1 compression ratio. Driven enthusiastically, there is no doubt that this 735i is a tremendously fast executive express, rushing from rest to 60 m.p.h. in 7.9 sec. despite the inevitable, mild wheelspin on dry tarmac. 70 m.p.h. is reached in 9.9 sec. and 80 m.p.h. in 13.1 sec. We have frequently reported in the past about the smooth, refined characteristics of the BMW six-cylinder engines and this, unsurprisingly, was the smoothest we’ve yet sampled and its low mechanical noise levels, allied to the fairly supple ride with minimal drumming and road noise transmitted to the occupants, makes for an impressively silent environment in which to be whisked along the autobahns of Europe. As for the behaviour of the new automatic gearbox, there is never any trace of sudden snatch from any of the changes, up or down, even though its very sensitivity to throttle openings can make it move backwards and forwards between third and fourth as a result of very minor changes in pedal pressure. Of course, one does have the option of simply moving the selector to ‘3’, thereby switching to a normal three-speed automatic arrangement all the time, without that overdrive fourth ever coming into the picture.

Quiet, refined running is only part of the BMW Package, of course, and considerable effort has gone into the task of “sharpening up” what some people still regard as the rather ponderous handling of this 735iA. The rear suspension has been modified to incorporate semi-trailing arms fitted at 13-degrees rather than the former 20-degree arrangement, this change making the 735iA fall into line with the specification of the 528i and 6-series coupés. This, in conjunction with a stiffer anti-roll bar, is intended to instil a considerable improvement in the car’s handling characteristics, and I have to confess that on dry roads, shod with its 205/70VR14 Michelin XWX radials on alloy rims, this 735iA exuded enormous confidence, sure-footedness and stability. It was only really on wet surfaces that one became aware of a nervousness which can provoke the sudden onset of unwanted oversteer when pressing-on hard on twisting road. As a high speed motorway cruiser the 735iA is really beyond reproach with excellent directional stability and response from the power assisted recirculatory ball steering system, but on twisting secondary roads I still wasn’t totally confident when positioning this big machine at high speeds. One could easily be accused of subjecting the 735iA to a style of use for which it’s not really intended, but at the end of the day I remained unconvinced that it matched the corresponding ‘S’ class Mercedes-Benz in the chassis department, even though it quite comfortably out-performs the 3.8-litre V8 saloon from Stuttgart. However, it is certainly worth re-emphasising the remarkable benefits afforded by the 735iA’s ABS braking system, the effectiveness of which continues to astound and amaze even those who thought they were fully used to it.

Aerodynamic improvements have been incorporated into the 735iA profile, including a slightly revised grille, a front spoiler below the bumper (which incorporates foglamps) and fairings round the front pillars, all these adding up to a reduction of 9 per cent in terms of drag. BMW claims that these modifications improve the fuel consumption of this 31 cwt. saloon by 6 per cent and, indeed, our overall figure of 20.9 m.p.g. is extremely good for a car endowed with this sort of performance — and comes out very favourably when compared with the 19.1 m.p.g. average recorded from the last 735i tested by Standard House back in 1980, that being a five-speed manual gearbox example. The 22.4 gallon fuel tank endows the 735iA with a range of almost 400 miles, a worthwhile feature for Continental touring.

Internally, this big BMW is equipped and finished to a very high level indeed, although there are no drastic changes to be seen in the layout of instruments and minor controls: as with most high quality cars, BMW interiors tend to evolve subtly and slowly as the years go by, not dramatically or suddenly. The four-spoke steering wheel is pleasantly thick-rimmed and, through its upper segment, the driver is faced by clear and concise instrumentation situated behind a non-reflective screen. The speedometer on the left is optimistically calibrated to 150 m.p.h. and the matching rev. counter red-lined at 6,200 r.p.m. Between these two large dials are situated the fuel contents and water temperature gauges in addition to the barrage of warning lights which indicate the car’s imminent need for servicing (five green, then amber and red, depending on how close the 735iA is to its scheduled check) while, to the right of the fascia, the now customary BMW check-panel retains the clever press-button system for checking fluid levels, brake pad wear and rear light bulb failure. The stalk controls remain the same as usual, with the left hand one dealing with indicators and headlight dip / flash facilities, while the two on the right control the windscreen wash / wipe (upper) and cruise control (lower). I don’t propose to labour my personal dislike of cruise controls yet again: suffice to say that I shy away from using such mandates for slack driving, just as I ignored BMW’s well-publicised on-board computer which can deal with every conceivable distance / time / m.p.g. calculation you might require, assuming you can understand or take the time off to work out how it functions. After a few miles, however, I was saved a guilty conscience since the computer ceased to work, along with the 735i’s interior light, so that was that!

Although such technical refinements as the ABS braking, inertia reel seat belts font and rear and headlight wash / wipers are fitted to the 735iA as standard equipment, it’s worth considering the cost of some of the other luxuries which further enhanced our test car’s £18,860 basic specification. The cruise control costs £384, leather upholstery is £788, limited slip differential £303, electric sliding roof £565, on-board computer £487 and the splendid electrically adjustable front seats £528, all of which mounts up to make the final cost well in excess of £21,000 which is a factor to be borne in mind for potential customers. As I said, the electrical seat adjustment is absolutely splendid, allowing driver and front passenger to adjust position, angle and height of their seats at the touch of one of four buttons on the centre console. This feature, for me, was one of the highlights of an interior design, the hallmark of which in complete ease of operation of all controls, including the distinctive push-button internal heating / demisting system. The seats themselves offer excellent support over long joumeys even though they feel a trifle soft and too sumptuous on first acquaintance. The boot is simply enormous and there are plenty of pockets, cubbyholes and trays in which to store the usuaI selection of superfluous bits and pieces that most people tend to hoard on a long trip. There is also the customary selection of tools fitted into a little fold-down tray inside the bootlid, a nice touch although one which may seem a bit unnecessary given the comprehensive “engine management and monitoring” system which seems well equipped to inform the driver what’s wrong almost before a failure has occurred!

Unquestionably, BMW have scaled fresh pinnacles with the 735iA, their saloon flagship arguably now better equipped and certainly quicker than most of its fellow high-priced machines from rival manufacturers. In addition to the effectiveness of that new automatic gearbox, which now means that the buyer doesn’t have to associate such extras with increased fuel consumption, the confidence conferred by the ABS braking system enables ground to be covered extremely quickly in what is, after all, a very large machine. There is no obvious Achilles Heel . . . and yet, despite BMW’s current high standard of finish, there are still very persuasive arguments in favour of opting for either Jaguar’s 4.2-litre XJ6 or the Mercedes-Benz 380. The Jaguar certainly hasn’t got the out-and-out performance, but notwithstanding its age, that Coventry-built six-cylinder engine is still a match for most in terms of mechanical refinement, while the XJ chassis rides brilliantly and is extremely quiet. There is an argument perhaps, that the XJ6 is on its last legs and its replacement is only just round the corner, but the Jaguar is still visually a far more graceful car than the BMW 735iA will ever be. The same applies to the beautifully aerodynamic profile of the ‘S’ class Mercedes-Benz, even though many people feel that, for all its refinement, the ride is too “coarse” and the steering a touch insensitive. It may be deemed a trifle flippant to condemn the 735iA on the basis of its looks, but I’m sure that many potential buyers will do just that. The 7-series BMWs have always been rather dumpy and ill-proportioned and no amount of cosmetic alterations will significantly enhance their lines. On balance, I found myself admiring the road manner of this 735iA although I never came to trust it implicitly close to the limit, an area in which I would have complete faith in the big Mercedes-Benz. Ultirnately, though, the 735iA lacks either the crisp styling of the Mercedes or the accepted elegance of the Jaguar: but if Munich ever gets round to putting that mechanical package into a fresh bodyshell, then Stuttgart and Coventry really will have something to worry about.

A.H.