Next Astra VXR to downsize engine

GM Opel’s decision to downsize the new-generation Astra K means the all-new replacement for Holden's current Astra VXR hot hatch will likely downsize its engine to 1.6 litres, do without the trick HiperStrut suspension and be unable to opt for all-wheel drive.

And while that might all sound a bit downbeat, those restrictions could also mean Opel’s HSV equivalent, Opel Performance Center (OPC), could be handed a more substantial role developing even wilder versions of the Astra more independently of the mothership.

The current VXR is a direct competitor for the likes of the Renault Megane RS. It is developed by OPC and powered by a 206kW/400Nm 2.0-litre turbo-petrol four-cylinder engine. It drives the front wheels only and relies on HiperStrut to separate torque and steering inputs.

The three-door Astra VXR has recently been relaunched in Australia as a Holden. It was previously sold here badged as an OPC when Opel was marketed directly here in 2012-13. The new-generation replacement won’t be previewed until next year and probably won’t be on sale in Australia until 2017.

The Astra K five-door, which goes on sale in Australia late 2016, is based on the GM’s new D2XX architecture, which has a smaller engine bay than its predecessor. That means the biggest engine that fits is the 147kW/300Nm 1.6-litre turbo-petrol four that is already sold in Australia in the existing Holden Astra GTC three-door.

At last week’s global first drive in Slovakia, the five-door Astra K’s chief engineer Marc Schmidt told motoring.com.au the smaller engine bay was key to enabling the new generation car to be smaller and much lighter, yet expand interior passenger room and maintaining luggage space.

“There are only three engine families now in the architecture and they have a tighter envelope, so that allows us to shrink the engine bay,” he said.

Asked if that meant the next OPC/VXR would have a tuned version of that engine, he said: “That (1.6) is at this point the ceiling. That is at this point the biggest engine we would be capable of packaging.”

But when asked if that meant OPC could also take a bigger engineering role developing Astra’s more distinct from the mainstream range, he replied: “I would say so”.

OPC currently has limited engineering capability and no assembly line – unlike HSV. But a driver for its expansion would be cars like the new 257kW/440Nm Ford Focus RS, which step up into the next performance class compared to a VXR.

“You can always do something really special for something really special,” said Schmidt. “But this time the something really special would have to be by itself under the architecture, so the basic efficiency is not compromised from the get-go. So it is a slightly different philosophy.”

The smaller engine bay also means the current HiperStrut can’t fit, while all-wheel drive hasn’t been package protected for D2XX. Instead, GM will develop its new generation of compact crossovers and SUVs on an architecture dubbed D2UX.

Schmidt said the development of HiperStrut had been driven by the weight of the current three-door Astra. But that is unlikely to be a factor next time round, as Opel is claiming savings of up to 200kg for the new-generation car.

“I think the reduction in mass and the current set-up of the suspension from a performance perspective we are very close,” said Schmidt. “The mass reduction itself is amazing relative to how the vehicle feels and handles, and that is why the Hiperstrut strut at this point is not happening.

Schmidt confirmed all-wheel drive capability had been eliminated because a significant amount of weight and cost would be added to the vehicle in return for a small amount of sales.

“As a result we were able to reduce the size of the tunnel in the rear which is why we have very good foot room, and we could rearrange the exhaust and mufflers which allowed us a clever solution. So it always has two sides of that story.”