As well as their common structure, the two cars will share many other costly sub-systems. These include the electrical architecture, climate control system, basic suspension layout, electronic chassis systems and innumerable hidden parts, such as seat frames and door locking mechanisms.It’s also likely that the Porsche will share its transmission with the Audi because the longitudinal unit used in the 911 and Boxster is thought to be too costly.
Not much is known about the flat-four engine at this stage, but Porsche sales and marketing boss Klaus Bening told Autocar earlier this year “That there is a clear trend towards downsizing, using smaller powerplants and supercharging. We will find our own conclusion to downsizing”.
Using today’s flat six as a starting point, a new flat-four engine would come in at just over 1900cc and could use either a light-pressure turbo or a supercharger. The light-pressure turbo set-up is already said to be under development for 2012’s 911.
It’s highly likely that such a unit would be good for about 250bhp. That’s virtually the same as today’s entry-level Boxster, although fuel economy would surely be better.
However, there’s little chance that the 356 and Boxster will clash because, according to one rumoured product plan, the next-generation Boxster and Cayman could be moved sharply upmarket.
Porsche has a financial problem with today’s Boxster/Cayman/911 line-up. According to an analyst’s report seen by Autocar, the cost of the components that make up one of the flat-six models is perilously close to the base price of a Boxster.
Indeed, the entry-level Boxster is only just over half the price of an entry-level 911, despite the two cars costing a similar sum to make.
Porsche can haul in significant profits from this model range in the good times — mostly thanks to the huge margins delivered by the high-end 911s. However, when combined sales fall below 50,000, the profitability of the flat-six model line is badly dented.
In the wake of the 356 launch, Porsche would be able to make the 3.2 Boxster S that model’s entry-level car, priced at £40,000. This would help improve the profitability of Porsche’s sports car line, especially since sales are not expected to be dented significantly.
However, in the long run, all Porsche’s sports cars will probably be based on the 356’s steel and aluminium platform. Selling four flat-engined sports cars on the same basic platform at volumes of over 75,000 per year — plus 25,000 or so units from Audi’s R4 — would help secure the long-term future of Porsche’s most iconic models.
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