Mahle fits eSupercharge 1.2-litre to VW Golf

Mahle Powertrain’s Northampton (UK) engineering team has replaced the standard 2-litre turbocharged engine in its donor VW Golf GTi, with the latest development of its 1.2-litre downsizing engine.

 The new power unit harnesses 48V eSupercharger technology coupled with an innovative belt integrated starter generator (BISG) to deliver high performance combined with fuel efficiency and reduced emissions.

The car will be at the Low Carbon Vehicle (LCV) event which is being staged at the  Millbrook Proving Ground, Bedfordshire, UK  (14-15 September, 2016). Visitors will be the first to see the eSupercharged downsized demonstrator vehicle on the road.

First unveiled at Cenex LCV 2015, the past year has witnessed further development of Mahle Powertrain’s groundbreaking demonstrator vehicle, which signals a bright future for mild hybrid gasoline engines. This year’s event sees the 48V equipped vehicle take to the test track for the first time.

Mike Bassett, chief engineer for R&D at Mahle Powertrain, comments: “Other key engine developments that have been successfully integrated since LCV 2015 include Mahle’s ECU (MFE), which plays an important role in both engine management and electrical system control simultaneously. This development control unit, including bespoke software, enables extremely rapid and flexible functional integration and comprehensive implementation of multiple control processes.”

In addition to eSupercharge and 10kW rated BISG, the 48V architecture used in this demonstration car comprises a three-cell, advanced lead acid, 48V battery pack and a pair of DC/DC converters (to maintain the state of charge of the 12V battery).

Real-world road tests, drive-ability and emissions calibration on the demo vehicle are currently ongoing and initial performance results are encouraging.

When compared to the baseline data (based on the standard 2-litre Golf GTi), the test vehicle is achieving a 22 per cent reduction in CO2 emissions. In terms of specific power, the Mahle engine produces an impressive 160 kW/litre (> 260 bhp), compared to the baseline of 100 kW/litre.

The low-speed torque generated by the almost lag-free eSupercharger enables a 0-100 km/h time of 6.4 seconds. While some of these figures are yet to be fully verified and tested, this eSupercharge engine has already shown significant potential as an attractive solution for mild hybridisation.

One of the characteristics of the eSupercharge downsizing engine is its ability to deliver steady state torque even at engine speeds as low as 1,000 rev/min. While the original turbocharged, gasoline donor engine typically produces 23 Bar BMEP at 2,500 rev/min, the MAHLE Powertrain unit generates 33 Bar BMEP with no evident lag. 

Mahle’s application of 48V eSupercharge to its 1.2 litre engine achieves the same acceleration as a 2.0 litre Mk 7 Golf GTi, while significantly reducing CO2 emissions and improving fuel consumption.