Lamborghini's push to produce its fast, edgy, four-door Estoque looks to have reached critical mass after senior Audi executives threw their support behind the Lambo limo this week.
Senior sources at Audi confirmed that the V12-powered super sedan with the four-second 0-to-100kph sprint would be exactly what Lamborghini needed to more than double its sales and finally grant the Italian supercar maker its financial independence.
The comments are the most positive indication yet that the on-again, off-again saga of the Sant'Agata brand's third model line is back on, but senior Audi management has done more than comment on the Estoque. By unofficially confirming production plans for Audi's own A9 limo-coupe, it has also given Lamborghini a production chassis to put beneath the Estoque concept car from the 2008 Paris Motor Show.
Lamborghini boss Stephan Winkelmann has been greeted with cynicism whenever he has mentioned his third model line, yet Audi officials now appear to have finally given conditional support to the project.
"Mr Winkelmann has said that Lamborghini needs a third model to give the brand a product cycle with fewer gaps in it, and he's absolutely correct in what he says," one senior Audi spokesman said.
"It's something Lamborghini needs, but it will need to be managed very carefully to remain a worthy Lamborghini."
Even though Lamborghini won't want the Estoque's future overshadowing the imminent launch of its all-new V12 Aventador supercar, the comments are a fillip to the Italian company, which has struggled to retain its sales peak of just over 2,000 cars a year during the global economic crisis.
"This sort of car will add something like 2,000 to 2,500 cars a year or even more to Lamborghini," the Audi source said.
"If you look at the only company near to Lamborghini in the way it works, it must be Ferrari, and Ferrari is financially independent at 5,000 cars a year. That's the region the Estoque will put Lamborghini in.
"That's got to be the goal for Lamborghini: to have solid financial footing and a constant renewal in the model cycle, which you can't do with two cars. So that's why it really must have three."
The super sedan is likely to be built with both V10 and V12 engines and will have Lamborghini's traditional all-wheel drive, but Lamborghini's engineers will need to work creatively with Audi's chassis people.
"Lamborghini is about performance and it's about design, so the Estoque will need to have those things and, I think, be reasonably faithful to the concept car," the Audi source insisted.
"That means that, a lot of the chassis of the A9 will be able to work for it, but the front end will need to be much lower if it will stay with the concept, so there will be a lot - a lot - of reworking with the chassis engineering people there.
"They will need to be very, very creative with the packaging of the engine and gearbox and the space-frame design and, perhaps, even the materials they use at the front of the car.
"We have to find a solution to fit the traditional Lamborghini styling. We have to make the bonnet lower and flatter. The packaging of the engine and the suspension and the chassis will be critical and that's what we're all experimenting with right now because it's the only real question mark."
Part of that creativity could include designing and building the entire front-end structure out of carbon fibre from the shiny new facility Lamborghini set up to build the Aventador's chassis, which would add tremendous chassis rigidity and crash safety while still allowing Lamborghini's exterior designers enough flexibility to replicate the concept car's striking nose.
Faithfulness to the Estoque concept car also means the production version will be a four-seat limousine, much like the A9 on which it will share its core chassis.
"Designing a supercar from a clean sheet of paper is one thing, but a limousine that people will drive to work every day and carry the family in over the weekend, well, that's a different thing, and Lamborghini doesn't have the financial or engineering resources to do it themselves," the Audi source confirmed.
"There is no choice if they want a third line but to share the engineering with us and let us help. After all, we've got more experience at four-door cars than they do."
Sources at Lamborghini insist the car can be built with the all-new, 6.5L V12 that will punch out 700hp in Aventador trim. Yet, the need to manipulate the torque curve to provide strong step-off torque in city situations will mean the horsepower will probably be both reduced to about 650 and it will also arrive as much as 500rpm earlier than the Aventador's 8,500rpm power peak.
Yet the payoff will be in pulling the torque peak down from the big supercar's 6,000rpm peak to closer to 4,500. The conversion of a supercar engine to a limousine engine is a challenge that has, in recent times, only been faced by Maserati, which converted the Ferrari F430's V8 into both 4.2L and 4.7L engines for its Quattroporte.
The gearbox is an easier question to solve, with the adoption of the A9's double-clutch unit being the clear favourite, while it will also adopt the Haldex IV all-wheel-drive system used in the Aventador.
Another clear favourite is a suspension controlled by an adaptation of the R8 V10's magnetic ride suspension system, which Lamborghini believes suits its character better than air-suspension.