Volkswagen Group in sportscar stoush

Audi, VW and Porsche are nutting out the details of a new three-way mid-engine sportster platform Appearing in e-tron form at last year's Los Angeles motor show, Audi's R4 platform made quite a splash. The electric powertrain has been shelved for now, but recent reports have had it looking increasingly likely the mid-engined sportster would reach the market with a choice of 2.0 litre diesel and 1.6 or 1.4 litre petrol engines.

Now UK magazine Autocar has reported that with its expansion into three different branded products the project is stalling amid arguments over the choice of aluminium alloy (ala Audi's spaceframe) or pressed steel monocoque body construction.

The plan is to assign the new platform duties under Audi's R4, a production model emanating from the BlueSport concept (pictured) rolled out by Volkswagen at last year's Detroit show, and a new low-ender from Porsche, designed to slip in under the Boxster.

Parent company Volkswagen is working on feasibility studies looking at the production costs and logistics for each, "high ranking Audi insiders in Ingolstadt" have told the mag. It boils down to questions of weightier but cheaper steel versus lighter but costlier aluminium alloy and the price at which each could reach the showroom. The e-tron concept shown in LA used and alloy spaceframe.

"The reaction to the e-tron concept has been overwhelming," an Audi insider told Autocar. "We're weighing up all the options and possibilities. There's no real time pressure because we're not replacing an existing model but establishing a new one."

"Scale is important to a project like this," another Audi source told the mag. "But with three different car makers working to a common goal, the chances [of it getting the go-ahead] look good."

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