No other engine,
however recent, can offer such a high torque delivery at
such a low rpm. All things considered, the new JTDM offers
exhilarating driving satisfaction that is difficult to
match. This achievement is also borne out by the
acceleration values (from 0 to 100 km/h in just 9.9 seconds)
and the top speed (198 km/h). Combining the new injection
system with new-generation variable geometry turbo engines
also completes an absolutely outstanding technological
picture.
In the same way,
the 120 bhp 1.6 incorporates the most advanced exhaust gas
treatment technologies, namely a Close Coupled Diesel
Particulate Filter and an integral EGR (Exhaust Gas
Recirculation) system that improves control of temperature
and gas flow, simultaneously guaranteeing lower emissions
and low fuel consumption. This set of solutions ensures the
power unit is Euro5-ready well ahead of the date on which
the regulation enters into force: this is the best example
of the great commitments made throughout the Fiat group to
ensure environmentally-friendly mobility.
The 120 bhp 1.6
JTDM engines are combined with a six-speed manual gearbox
that ensures lower rpm particularly at highway or motorway
speeds, with the twofold advantage of less noise in the
passenger compartment and a reduction in true fuel
consumption.
78 bhp 1.4 aspirated engine
Alfa Romeo
developed this engine specially in order to produce a car
designed particularly for young people, i.e. with limited
power capacity but still able to reflect all the qualities
of handling and driving satisfaction that are expected of an
Alfa. The aspirated 1.4 engine has a power output of 78 bhp
(58 kW) at 6000 rpm and a maximum torque of 125 Nm at 4250
rpm. The weight/power ratio expressed by this particular
engine took its inspiration from Italian laws introduced for
those who have recently passed their driving test, that
limit the specific power over tare ratio for drivers who
have recently passed their driving test to 50 Kw/t. This law
was originally intended to enter into force in July 2008,
but this has now been postponed to January 2009.
Slick, reliable gearboxes
A range of reliable, sturdy and sophisticated gearboxes has
been developed to match the engine range on offer for the
Alfa Romeo MiTo: the new vehicle can be fitted with three
variants: M32: manual, 6-speed for the 155 bhp 1.4
Turbopetrol and the 120 bhp 1.6 JTDM; and C514: 6-speed
manual gearbox for the 78 bhp 1.4 engine.
All the gearboxes share a dual cable external mechanism that
ensures slick manoeuvres and noiselessness without
transmitting mechanical vibrations through the linkage. The
details: the new-generation external linkage is
technologically advanced due to the extensive use of
high-performance technopolymers to guarantee the various
qualities of strength, weight and self-lubricating
capability. Bench testing under extreme weather conditions
also guided the development of materials, couplings and
processes to ensure product toughness and reliability. The
new linkage was also designed to ensure system and
performance characteristics of maximum comfort and
manoeuvrability. To achieve greater comfort through maximum
mechanical filtering action, a new distribution pattern was
adopted for an inertia mass distribution that is strongly
shifted toward the gearbox.
Among the
engineering features worthy of highlighting, the gear casing
and clutch casing have been optimised in terms of lightness
and noise absorption though FEM (Finite Element Method)
computing techniques. The first and second gears, i.e. those
most commonly used by motorists, also come with triple cone
synchronisers (double-cone on the C514) that require 40%
lower engagement effort than a conventional single-cone
type.
In detail, all
the gear boxes fitted to the Alfa Romeo MiTo feature an
internal gear control system on four selection planes with a
central positioner. Lubrication is dynamic with oil flows
channelled. The advantages include: lower wear and higher
efficiency during torque transmission and low temperature
manoeuvrability.
The quality and
reliability of these components is also guaranteed by the
great care taken at the assembly stage, when each component
is pre-tested and electronic measurements are carried out on
the parameters that define efficiency, flexibility and
clearance.
6-speed gearbox (C514) for
the 78 bhp 1.4 unit
Increased
acoustic comfort, lower shift effort even when cold and
greater gear engagement precision. These are the benefits
offered to the motorist by the C514 gearbox (transverse
configuration with two shafts in a cascade and differential)
that underwent improvements to the following parts: gears,
synchronisers, lubrication, inner gear linkage and clutch
control.
When paired with
the 78 bhp 1.4, the 6-speed device represents the latest
upgrade to the gearbox in terms of transmissible torque (125
Nm). The use of higher quality materials for the gears, the
use of an upgraded differential with oversized bevel gears
and a bolted connection between box and ring gear make for
the greatest reliability. The main qualities are excellent
gearshift manoeuvrability, low shift noise and low weight.
6-speed gearbox (M32) for
the 1.6 JTDM and the 1.4 Turbopetrol
Increased
acoustic comfort, lower shift effort even when cold and
greater gear engagement precision. These are the benefits
offered to the motorist by the M32 gearbox (transverse
configuration with two shafts in a cascade and differential)
that has undergone improvements to the following parts:
gears, synchronisers, lubrication, inner gear linkage and
clutch control.
The unit is
available in a 6-speed version and can withstand high torque
values (320 Nm). This makes it the ideal choice for
higher-performing engines: the 120 bhp 1.6 JTDM and the 155
bhp 1.4 Turbopetrol. It is also fitted with a gear linkage
that features a selection travel limiter to safeguard more
effectively against involuntary engagement of reverse and to
increase fifth and sixth gear engagement precision. |