Fiat: Twinair hybrid under development; 500 Twinair driven
October 28, 2010 § 1 Comment
Fiat is working on a hybrid version of its Twinair powertrain. The clever little two-cylinder, 875cc engine is “well-suited to hybridisation”, say Fiat Powertrain Technologies spokesmen, and although the system is still some way off production, “we’re really working on it. It’s in the concept stage”. The super-compact engine, motor and transmission all fit neatly under the 500’s tiny bonnet; it will use Fiat’s new DCT (dual-clutch) Dualogic gearbox.
Before the hybrid, however, come new versions of the Twinair engine, billed by Fiat as “the greenest gasoline engine in the world.” A bold claim, but the Euro 6-compliant 85bhp turbocharged version now on offer in the 500 returns 69mpg and emits just 95g/km of carbon dioxide, beating comparable Toyota iQ, Smart Fortwo, Ford Ka and Mini First models hands down on economy, emissions and performance. It’s combined with stop/start (a specially-tuned system much-improved from the jerky, unintuitive tech in the earlier 1.2 Start&Stop), and when the Dualogic gearbox comes as an option next year, economy and emissions will be better still. 2011 also brings a naturally-aspirated (non-turbo) entry-level version of the engine giving 65bhp, plus a sports version (105bhp).
FPT says that the use of the Multiair valve control system, along with a specifically-developed turbocharger, has allowed for a higher compression ratio (10:1) than usually seen in engines of this type. Refinement and NVH (noise, vibration, harshness) are well-controlled thanks to a balancer shaft, giving just a distinctive two-cylinder burble and a whoosh of the turbo.
The benefits of the small-capacity twin include high torque from low engine speeds, plenty of mid-range strength, and relaxed cruising speeds, aided by a high-set fifth ‘overdrive’ gear in the manual models. The manual-transmission 500 Twinair is a lively, rewarding drive, sharp to accelerate and nip around town, with sufficient reserves for overtaking on faster roads and keeping pace at motorway speeds.
CNG (natural gas) fuelled versions will be made for markets where this fuel is popular, and further into the future, the indirect-injection Multiair system will be supplemented with direct injection, a technology initially developed in parallel by Fiat for its larger engines. “The two technologies (Twinair and direct injection) can live together”, said an FPT spokesman. “They will probably be matched in the future, but at this stage, we didn’t need to do it.”
Fiat’s clearly ambitious in its plans for the Twinair engine, which must be more expensive to build than its four-cylinder line-up, what with its advanced technologies, features such as chain-drive in place of a cheaper rubber drive belt, and the need for a new, dedicated production line (they’re not talking figures on all this). But the Polish plant where the engine is built is being prepared to make 450,000 units a year, with a capacity of 800,000 possible, and economies of scale will surely be achieved.
Expect this engine to feature across Fiat’s A- and B-sector products (Panda and Grande Punto, for a start, not to mention the rumoured upcoming city two-seater), and at a later date, Fiat plans to license it and supply it to other manufacturers (probably including Ford, for the Ka). In the UK, it’s now available across the 500 line-up, in all models including the 500C convertible and special-edition byDiesel and matte-paint Blackjack (pictured).