GMS 2017 Vauxhall Insignia 2
Bruce Newton8 Mar 2017
NEWS

Why no twin-turbo Commodore?

Insignia unveiling delivers Opel chiefs opportunity to explain why no hi-po twin turbo V6

Opel engineers and designers have defended the decision not to allow space for a turbocharged V6 engine under the bonnet of the all-new Insignia large car.

The Insignia, which was officially revealed at the Geneva motor show yesterday, will come to Australia as the first imported Holden Commodore in 2018.

But it is limited to a 230kW/370Nm 3.6-litre naturally-aspirated V6, leading Holden to retire the SS sports badge linked with V8 engines and preventing Holden Special Vehicles from producing a version of the car.

During presentations by Opel design chief Mark Adams and the Insignia’s chief engineer Andreas Zipser to Australian media at this week’s Geneva motor show, the level of Holden involvement in the project from its earliest days in 2012 was emphasised. While that co-operation has been highlighted as playing a role in the naturally-aspirated V6 fitting in the car’s engine bay, the additional plumbing for twin turbochargers was not accounted for.

GMS 2017 Vauxhall Insignia 2

Holden and HSV experimented in Australia with making such an engine fit but gave the task away as too complex and expensive to justify. As for the V8 engines that have been a bulwark of hi-po Commodores and sustained HSV for generations… Never a chance.

So why wasn’t the additional space for a turbocharged engine -- that would offer significant performance and marketing upsides – ‘baked’ into the program when Holden and HSV clearly would benefit from it?

“One of the things we have tried to do with the car is significant weight reduction and whenever you are going after weight if you add too much bandwidth into everything, you carry is what you call ‘scar mass’,” explained Opel design chief Mark Adams.

“Then the inherent car is too heavy relative to the overall performance. So there comes a point when we start tipping the scales too far the other way. That is all a trade-off decision and a part of that dialogue is all about finding the right balance of the car,” Adams said.

GMS 2017 Vauxhall Insignia 3

“If we add everything in and say ‘now we have got all the specifications we need’, then the overall car becomes too heavy, less agile, less balanced. So it’s all about finding that balance,” he said

Asked if it was a design or engineering call to not package protect for a V6 twin turbo, Adams described it as a “company call”.

“Design and engineering are part of the thing and we have to make leadership decisions all the way along on these things… We see the pros and the cons and we make choices. Designing and engineering a car you make choices every day.”

Adams was clear that the decision on applicable engines was made early in the Insignia program, driven by the car’s move to GM’s new E2XX architecture.

“They have to be baked into the architecture because what you can’t do is be messing around with the architecture when you are designing the final car, because then you are in trouble,” he stated.

The installation of the V6 engine in Insignia has been claimed as a Holden initiative because for Commodore. Opel will only offer four-cylinder turbocharged powertrain options for Insignia in Europe. But the V6 is also likely to turn up in the next Buick Regal, although no-one from Opel can confirm that with media as that car won’t be revealed for some weeks.

Zipser was clearly somewhat bemused about the line of questioning regarding the lack of a turbocharged V6.

“What I would say is look to the overall package of the car. One of the big advantages of the car is that it is getting very light,” he responded.

“So for me this is a different interpretation for the next generation Commodore -- we are reducing drastically weight… It is 200-300kg lighter [than the current Commodore],” Zipser continued.

“What I am saying is that we customise the vehicle with the weight reduction on to performance… If you talk about single turbo or twin turbo ,at the end of the day what counts is driving performance and the driving behaviour.”

Zipser said the front-wheel drive 2.0-litre turbocharged petrol engined version of the Insignia five-door hatch should be capable of recording low 7sec 0-100km/h times. Holden says that will make it the quickest base model Commodore ever built.

The V6, which will mate with a nine-speed auto and Twinster all-wheel drive system is expected to clock 0-100km/h times below 6sec. Current 6.2-litre Holden V8 Commodores are in the low fives, while supercharged V8 HSVs are in the 4sec bracket.

Share this article
Our team of independent expert car reviewers and journalistsMeet the team
Stay up to dateBecome a carsales member and get the latest news, reviews and advice straight to your inbox.
Download the carsales app
    AppStoreDownloadGooglePlayDownload
    App Store and the Apple logo are trademarks of Apple Inc. Google Play and the Google Play logo are trademarks of Google LLC.
    © CAR Group Ltd 1999-2024
    In the spirit of reconciliation we acknowledge the Traditional Custodians of Country throughout Australia and their connections to land, sea and community. We pay our respect to their Elders past and present and extend that respect to all Aboriginal and Torres Strait Islander peoples today.