BMWCAR_0907_B7BiTurbo.pdf

Premier Cru

As well as making some fine wines Alpina also produces some rather good motor cars and

its B7 Bi-Turbo has to be one of its best creations to date

Words: Bob Harper Photography: Max Earey

Y ou could be forgiven for thinking that

4.9. A standing kilometre time of 22.9 seconds is the

same as the M5 Touring a machine that, according to

the stats, has the same power output yet weighs over

150 kilos less and has a smaller frontal area to

contend with. It seems that Alpina is being overly

conservative with its figures as it doesn’t wish to bite

the hand that feeds it, given the company’s very close

relationship with BMW, and that perhaps the B7’s V8

may well be right up there (or beyond) what BMW

claims for the X5 and X6 M’s similar powerplant.

So, while the block and head may look virtually

identical to the 750i’s V8 and share the same capacity,

they hide Mahle pistons and while the twin-turbos are

installed in the same location they have been specially

Garrett with 44mm vanes for additional boost.

A huge proportion of the B7’s development budget

was swallowed up by a need to make cooling as

efficient as possible and as a result the three bespoke

Behr intercoolers that nestle behind the reworked

front spoiler are 35 per cent bigger than those fitted

to the 750i. To give you an idea of the lengths Alpina

went to to ensure optimum cooling it discovered

during wind tunnel testing that at a certain speed a

venturi effect in front of the block was causing air to

be sucked back out of the kidney grilles which was

having a major effect on aerodynamic efficiency. Thus

it redesigned the plastic vanes behind the kidneys,

the tooling for which cost a cool

BMW had made life a little easier for

Alpina by opting to fit twin turbos to the

750i, the base for Alpina’s latest über-

cruiser. With the E65 generation B7

(along with the B5 and B6) Alpina had to develop

the supercharger system that hiked power to over the

500hp mark but with the new car already being

turbocharged all Alpina would need to do was up the

boost, slap on some trademark alloys and

aerodynamic addenda and the job’s a good ’un.

However, as we should know by now, Alpina definitely

operates on the ‘if a job’s worth doing, it’s worth

doing well’ school of thought and there’s a hell of a

lot more to the new B7 Bi-Turbo than meets the eye.

And as I join the Autobahn I can feel all that Alpina

fettled goodness coursing through the B7’s veins.

Pootling around the outskirts of Buchloe it’s a paragon

of understated smooth-riding cruiser, with just a hint

of V8 menace at initial start-up to remind you that

this is a thoroughly reworked machine. On the move

with gentle throttle inputs all is as calm and refined as

you’d expect from a nigh on £100,000 7 Series, but

light the blue touch paper and all hell breaks loose.

Snapper Earey is following in a B3 Bi-Turbo, itself

no slouch, but even I’m astonished by how quickly it

turns into a speck in the mirror of the B7. Quick just

doesn’t cover it. Introduce the loud pedal to the

carpet and the two-tonne B7 simply launches itself at

the horizon with a ferocity that just shouldn’t be

possible in such a large machine. If I’d been driving it

at night I really wouldn’t have been surprised if the

lights outside the car had taken on a Star Trek-esque

warp drive demeanour. It’s a carefully thought-out

blend of speed, the sensation of speed and just

enough V8 grunt to keep the inner enthusiast happy.

The B7’s unrelenting thrust is, naturally enough,

down to its engine and while it shares the same basic

architecture as the BMW unit on which it’s based,

there’s been a hell of a lot of work involved in

creating a V8 whose figures are, in typical Alpina

fashion, wildly conservative. Claimed output is 507hp

at 5500rpm while torque is a prodigious 516lb ft

available across a 3000 to 4750rpm rev band. You

can bet your bottom dollar that the B7’s V8 will

produce these numbers on the hottest day of the

year in Death Valley, so on a cool Bavarian morning

they feel like a hell of a lot more. It doesn’t take a

rocket scientist to realise that there’s more to the

engine than Alpina’s figures would suggest, as despite

weighing in at the best part of 100 kilos more than

the previous generation machine it will accelerate to

62mph from a standstill in 4.7 seconds instead of

70,000!

The result of all the engine work is a unit that’s not

only immensely powerful and torque rich while being

cultured and refined when you want it to be with a bit

of an animalistic dark side when you indulge in some

full throttle tomfoolery, but one that’s also remarkably

efficient, parsimonious and clean. Naturally enough

it’s EU5 compliant and has a CO2 output of just

286g/km (that’s less than a 2005 X3 2.5i!) but it’s

the combined economy of 23.7mpg that’s the

amazing feat. On the extra urban cycle it’s claimed to

do 32.8mpg and while we didn’t manage to match

those figures, being less indulgent with the throttle

pedal would have seen us come close. For a two-

tonner with over 500bhp that’s quite remarkable.

The Bi-Turbo V8 is hooked up to a modified ZF

6HP26 TÜ six-speed automatic transmission that’s

similar to the one used in the previous generation B7.

The gearsets come from a variety of sources but the

smoothness of the resulting gearchange can’t be

faulted, and when you’re on a charge it’ll seamlessly

swap ratios in a couple of hundred milliseconds with

hardly an interruption in power delivery. In an ideal

world Alpina likes to use as many off-the-shelf BMW

components as possible to keep costs down, but

€

BMW car

BMW ALPINA B7 BI-TURBO

the two-tonne B7 simply launches itself at the horizon with a

ferocity that just shouldn’t be possible in such a large machine

JULY 2009

BMW ALPINA B7 BI-TURBO

ENGINE: V8, Bi-Turbo

CAPACITY: 4395cc

MAX POWER: 507hp (373kW) @ 5500rpm

MAX TORQUE: 516lb ft (700Nm) @ 3000-4750rpm

0-62MPH: 4.7 seconds

WEIGHT: 2040kg

STANDING KILOMETRE: 22.9 seconds

TOP SPEED: 174mph (280km/h)

ECONOMY: 23.7mpg

EMISSIONS: 286g/km

PRICE: £95,900

CONTACT

Alpina GB

Tel: 0115 934 1414

Web: www.alpinabmw.co.uk

BMW car

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