The changes will allow Vauxhall and Opel to operate at 112 per cent of its capacity on two shifts or 87 per cent on three shifts, giving it the flexibility to increase production if demand increases.
As previously announced, the UK's Ellesmere Port plant will not be significantly affected, while production at Luton is guaranteed until 2013, despite the loss of around 500 jobs.
Luton currently builds the Vauxhall/Opel Vivaro van in conjunction with Renault, and Reilly confirmed he is in talks with Renault to extend that agreement beyond the end of 2012. He added that if the deal is not extended, he will investigate building an alternative vehicle at the plant.
Reilly also revealed that the £9.7bn of investment will be targetted at three key areas: investment in new vehicles in areas where the company already operates, investment in fuel-efficient vehicles, spearheaded by the Opel Ampera, and assessment of possible expansion in the Middle East and Asia-Pacifc regions.
He added that any GM vehicles developed outside Europe that go on sale as Vauxhalls or Opels will be tested and developed at Opel's Russelsheim technical centre before going on sale.
The product plan reveals a total of 12 new product launches by the end of 2011, which Reilly says will mean 80 per cent of Vauxhall/Opel's products will be three years old or less by 2012. Beyond that, Reilly reiterated the company's eagerness to build a small, sub-Corsa-sized vehicle.
The new product offensive includes the launch of the Ampera in 2011, a car that Reilly has identified as a key vehicle for Vauxhall/Opel because of its pioneering technology and the potential for spin-offs from the technology. As a result, £880,000 will be invested in fuel-efficient technology by 2014. This will include developing an 'environmental' concept car, which will be displayed at this year's Geneva motor show.
Reilly added: "We now have all the necessary ingredients for a successful future in place: a motivated workforce, a new and accountable company culture, a product offensive based on innovative and highly fuel-efficient technology, a competitive cost structure based on conservative volume assumptions, a dedicated management team and the support from so many stakeholders.
"Now it is up to us to prove we can do it. I am confident that we will."
Reilly also confirmed that he was in talks with Sherbank, a partner of Magna that was originally looking to buy Vauxhall/Opel from GM, to pay compensation for its costs on the failed talks. "It is looking to reclaim some of its costs, but there was no obligation to pay costs," he stated.
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