FFIRIRSSTT D DRRIVIVEESS
3 1 JULY 2019 AUTOCAR.CO.UK 27
TESTER’S NOTE
Given it was 40deg C,
the A’s brakes hold
up well on track, even
when the pedal goes a
little long. MP
`
As you might expect,
Mercedes has opted for
a lot of drive modes to
accommodate all this
a
Δ front wheel arch, the others bolted
around mostly under the body.
But AMG, Mercedes’ alternative
to BMW’s M Division, is, above all
else, an engine builder. Its un-woke
‘one man, one engine’ build principle
sees that each 1991cc four-cylinder
fitted to 45s is hand-assembled by
one technician at AMG’s Affalterbach
base before being crated to the
A-Class production line.
It’s a complex unit in itself, and
things get fairly complicated behind
it too. The engine drives through an
eight-speed dual-clutch automatic
gearbox to all four wheels, with
the rears via a propshaft which is
always turning at the geared speed.
Tw o c lut c he s e it he r side of t he r e a r
differential, recent Ford Focus
RS-style, distribute power left or
right as they see fit – which means
under acceleration and cornering,
really. In constant-speed cruisingthey’re pretty idle.
T he y c a n d i s t r i but e a s muc h
torque as the rear axle receives to
w h ic he v e r side t he y c ho o s e – up
to 100% of it per side. The system
c a n’t de l i b e r at e l y pu sh mor e t h a n
half of the engine torque to the rear
wheels, but in theory the back wheels
could be receiving more than 50%
of available torque if, say, the body
was heavily loaded on the way out of
a slippery corner and the fronts were
scrabbling. It rarely works like that,
though, and, if it does, for no more
than a moment.
As you might expect, Mercedes
has opted for a lot of drive modes to
accommodate all of this. Probably
too many, within a cabin that
already has rather a lot going on. It’s
designed pleasingly, though, with
lovely turbine-style air vents that I’m
very fond of and a high-resolutioninstrument pack and central screen.
But oh my, there’s some tech
overload. On the instrument
binnacle, pick one of the several
options for showing a speedometer
on the left, and you’ve still got seven
other choices for how the rev counter
looks to the right of it. There’s
another display in the middle of
those two, too. The steering wheel
h a s 17 but t on s or le v e r s at t a c he d t o it ,
and two of those are multi-function
track pads. And yet turning off the
l a ne k e e p a s si s t i s bu r ie d i n t he m a i n
centre screen menu.
I’ll go on. There are five drive
mo de s , or si x c ou nt i n g t he
customisable ‘Individual’ one,
which encompasses four ‘AMG
dynamic’ modes (how the stability,
transmission and four-wheel-drive
systems operate), three damper
settings, two exhaust modes(a lt hou g h t he s e a l s o v a r y b y d r i ve
mode) and two steering weights
which you can’t select yourself –
some settings are barely heavier than
the others. ESC can be on, in Sport,
or all off. And there’s a ‘drift mode’ (it
doesn’t disconnect the front wheels
but put s e v e n mor e e mph a si s on a n
outer rear wheel) and launch control.
Apparently some markets really
like all this. I just wanted to trust
what the engineers thought was best
and have the relative simplicity of a
Alpine A110 or a BMW M2. But no ◊
The A45 rolls off the regular A-Class production line but sports wider wings and tracks, while its 416bhp engine is hand-assembled at AMG’s HQ