@wheelsaustralia 15
of the firewall. The intake is now at
the front of the engine, requiring less
plumbing, and a lower bonnet improves
aerodynamic efficiency.
The heavily boosted 2.0-litre four-
cylinder engine runs a bore increased
to 83.0mm, while the stroke remains
at 92.0mm for a swept volume of
1991cc. The compression ratio has
been raised to 9.0:1, while the twin-
scroll turbo pumps 30.5psi (2.1bar)
of pressure into friction-reducing
Nanoslide-coated cylinders. The
turbo runs at an efficient operating
temperature thanks to oil and water
cooling; the radiator cops its fresh air
via bonnet ductsandtheenginecover.
Boost pressureis monitoredwithan
electronic wastegate,whiletwo-stage
fuel injectionis a firstfora high-
performancefour-cylinder.
AccordingtoAMG,thepower
delivery is nowmorelikea naturally
aspirated engine.Thetorquecurve
has been bolsteredatlowerrpmfor
improved throttleresponse,while
there’s extrapullingpoweratthe
top-end due tothemorefree-revvingN A WORLD where Mercedes-
AMG has engineered a hot
hatch with 310kW and 500Nm
from just 1991cc, perspective is
vital. You’d have to think that
the masterminds behind the
originalVW Golf GTI would struggle to
fathom a humble hatchback with the
ability to monster supercars. Such is the
rate of progress that the original Audi
R8 V8 and 996 Porsche GT3 are both
outgunned by the upcoming A45 S.
Of course, the headline act is the
new, hand-built M139 engine. Its
310kW (in S guise, at 6750rpm) makes
it the highest specific output of any
series-production four-cylinder engine,
generating a staggering 155kW per
litre. Yes, the numbers beggar belief,
with the 0-100km/h dash completed
in 3.9 seconds and the hyper-hatch
rocketing to an electronically limited
Vmax of 270km/h.
One of the biggest changes behind
the new ‘shark nose’ is the fact that
the 160.5kg four-pot has been swung
around 180 degrees, with the exhaust
manifold and turbo now just ahead
I
THE DEVIL
IN DETAIL
UNCOVERING THE FINER
POINTS OF THE A45 SA45 S UNCOVERED
Whileothermarketswillreceivea base-
modelA45with‘only’285kWand480Nm,
it’snotslatedtomakeitswayDown
Under.Despitebeingdownonpower,the
0-100km/htimeincreasesbyonlya tenth
(to4.0seconds)andthetopspeeddrops
toanelectronicallylimited250km/h.The
A45S is expectedtoarrivein Australiain
Q1 2020 alongsidetheCLA 45 S,which
sharestheA45’smechanicals.Max power
‘Jet-like’externalair
ventsadda muscular
stancetotheA45S.
TheAMG-specific
grillefeatures 12
verticallouvres;yes,
it’sfunctional,directing
coolairtotheturbo.one
ANGRIER
FACE
Aggressivestyling
continuesattherear
witha largewingand
diffuserhousingbig
quadtailpipeswith
internalflutingand
AMGlettering.Get
usedtothissight.two
BABY GOT
BACK
A45S modelsgain
19-inchalloywheels
(8.5 inches wide)
wrapped in 245/
tyres. Braking is
improved with six-
piston calipers and
360mm front discs.three
WHEELS ARE
TURNING