This autumn, a new breed of V8-powered BMW 7-series will be imported to Britain. By their italic script, unchromed V12 grille and enlarged exhausts shall you know such a machine.
Confusingly, it will be marketed as the 730i (anticipated price £38,950), whilst the six-cylinder 730i continues at £28,800 and the 740i (£45,500) fills the gap to the sluggish V12 750i.
We drove the BMW V8s in manual three-litre and five-speed automatic four-litre formats, which demonstrated that BMW offers formidable competitors to Jaguar, Mercedes and Toyota Lexus. The eights are not as smooth as the legendary BMW sixes, but major on accessible power and driver/showroom appeal.
Aluminium V8s were a pioneering item in post-war Germany, BMW debuting its 501 saloon in 1954. That 2.6-litre, 90 bhp unit had blossomed to 3.2 litres and 160 bhp by the time it was phased out of production in the 1965 3200 CS, which retained pushrod valvegear. In 1992, BMW is back in the V8 arena, but this time dohc, four-valve cylinder heads have extracted 218 bhp from three litres and 286 from its four-litre brother (73 and 72 bhp per litre respectively).
These powerful competitors have the same 90 deg block angle as their ’50s predecessors, but any other links between BMW V8s separated by 38 years are in the minds of the PR people. Naturally, both new V8s share as many features as possible, but a steel crankshaft is at the heart of the differing dimensions, the smaller motor taking a cast iron shaft. Thus they share neither bore nor stroke, the 2997 cc unit operating on 84×67.6 mm whilst the 3982 cc comes courtesy of an 89 x 84 mm configuration.
Former Porsche 917 development engineer Reinhard Hofmann, now general manager of BMW powertrain development, tells us that the maximum cubic capacity for the V8 would be 4.4 litres. In my view, we are unlikely to see this in production until the V12 is cheered up beyond its present lacklustre torque and five-litre/300 bhp specification, probably by block enlargement rather than the four-valve-per-cylinder heads developed by BMW Motorsport for the McLaren F1 road car.
Bosch 3.3 digital motor electronics control each bank to induce a hearty unison, based on a 1-5-4-8-6-3-7-2 firing order selected to emphasise smoothness and a unique engine note, which is more BMW turbine than traditional American V8 in quality.
Following construction of 560 test V8s and over five million road miles, BMW felt confident enough to release the engines. Torque peaks at 4500 rpm, 214 lb ft for the three-litre and 295 in the automatic 740i. Performance claims are realistic, 0-62 mph taking at 8.5 and 7.4s in 730i and 740i trim. Top speeds are 145 and 149 mph respectively.
Far more important is that either model will lollop along at 70-100 mph with the radio whispering, yet audible. Even at 125 mph/4000 rpm in the four-litre, the occupants are aware only of wind and tyre noise as a measure of their velocity.
These two leviathans (the smallest weighs nearly 3800 lb) featured widely differing specifications that we can only highlight here. Our 740i came with full leather trim (a rather impractical light grey that BMW favours these days), wood inlays that I loathe and customers demand in this category, an excellent ZF five-speed automatic and myriad electronic ‘nannies’. These guard against wicked wheelspin (ASC) and bumping into things whilst parking (PDC parking distance control). I have to confess, I found the beeping parking device extraordinarily effective.
Our V8s had computers, which showed a tight Italian test route with a token motorway allowed 15.8-18.5 mpg at an average 55 mph in the bigger V8. The manual returned 18-21mpg at a slower average speed. BMW estimates a 19 mpg urban figure for the manual, 16.1 mpg for four-litre automatics.
On roads that veered from roughly cambered to concrete block motorway, the 7-series impressed us. We expected quality and a feeling of solid worth, but did not expect the 7-series to be such a driving pleasure. The automatic V8 showed fabulous overtaking ability in the sensitive ‘sport’ mode and the subjective feeling of overall engine smoothness aside we can now see little point in the BMW V12, for the V8 is altogether more responsive. There is only 14 bhp between them, and the V12 has always felt to be (comparatively) lacking in low to midrange pulling power, whereas the V8 always has at least 237 lb ft available between 2000-6200 rpm. The three-litre brought even greater driving pleasure, but this was simply because the terrain demanded the slick manual ‘box. Although both share a 6500 rpm red-line, the three-litre did feel marginally the smoother unit, although you have to work harder to release a minimum of 178 lb ft between 2600-6100 rpm.
Criticisms? We had to scratch our heads on this one. The typical customer would probably prefer a more absorbent ride than the settings that we enjoyed, and less tyre noise. Even so, BMW’s EDC (electronic damper control) option might help both driving styles. We might prefer the BMW V8 in a smaller car. Autocar and Motor has reported that BMW will fit the V8 in the 3-series, but the factory engineers repeatedly denied this. Besides, the M3 replacement is on schedule to offer a road-going 270-286 bhp.
That leaves the 5-series, and there were many heavy hints that this BMW combination would be fielded in LHD as the 530i/540i this autumn. Quite where that will leave the 340 bhp MS (now 3.8 litres and resolutely a 24v six) remains to be seen. If you are in the market for a larger saloon, one that offers that elusive blend of outstanding civility and stimulating speed, the 7-series has improved almost beyond recognition over the years.
The four-litre V8 makes it a very desirable automobile in any company.