Test of former flat-six performance model could have unfairly lowered its CO2 output

Porsche has been accused of manipulating UK emissions tests for the Cayman R, enabling the model to be rated with a lower CO2 output and therefore lowering its vehicle excise duty price for owners.

A report unearthed during a legal case for an unrelated safety issue states that the tests for the Cayman R, a hardcore variant of the previous flat-six-engined two-door, involved the car being driven off in second gear. By selecting that gear, the revs of the naturally aspirated 3.4-litre engine would remain lower, enabling the car to produce less CO2 than if it were to be driven off the line in first gear.

This, in turn, produced the car’s 221g/km CO2 rating in the UK, which is 7g/km lower than in Europe. The lower level ensured that the Cayman R cost £315 per year to tax rather than the £540 required for cars that emit 226-255g/km, according to the previous tax system.

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According to The Times, as many as 1500 British motorists who run or have run Boxster S, Spyder, Cayman R and Cayman S models could have paid less tax as a result of the test change in 2009. The report claims that this equates to a loss of £3 million for the Treasury.

Autocar contacted Porsche for comment, but a spokesman said: “No comment can currently be made because it is the subject of ongoing legal proceedings." Porsche’s legal proceedings currently include a case in its home country of Germany, where a company board member is being investigated for potential involvement with the Volkswagen Group’s Dieselgate scandal.

Like group stablemate Audi, however, Porsche’s involvement has so far been linked to its use of VW diesel engines rather than an internally produced unit. 

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Comments
18

14 May 2018

Have more tricks up their sleeves than Paul Daniels!

typos1 - Just can’t respect opinion

14 May 2018

This affects the manual transmission 987.2 version.  Not the 981 model.

14 May 2018

So MPG varies by jurisdiction ?

14 May 2018

.....and still we buy their cars in droves despite these companies' questionable morales, practices and behaviour. 

289

14 May 2018

....probably because nobody gives a toss about the emissions or a manufacturer lying to gat under some obscure threshold.... but everyone cares about wasting money by giving it to a bunch of thieving lying politicians!

14 May 2018

There is probably a lot more than the vw group that are chancing emission laws...shame that they have been caught. The emission laws don't make better cars. Maybe they do have a point about stopping global warning though (not)

14 May 2018

Sure the tax people will feel cheated but WTF! no one cheats us more than the government!! wake up petrolheads! we have been a cash cow for them for years and  continue to be so! the old quote comes to mind  "Don't steal, the government hates competition"

Madmac

14 May 2018
madmac wrote:

Sure the tax people will feel cheated but WTF! no one cheats us more than the government!! wake up petrolheads! we have been a cash cow for them for years and  continue to be so! the old quote comes to mind  "Don't steal, the government hates competition"

The government has to do it though. Any party in power would do it. It is something that has to be put up with (like the new MOT)

14 May 2018

If the car legitimately made that score (in whatever gear) without the software tricks, then it's a legit result.   I relly don't see what the problem is.

14 May 2018

You dont see the problem ? It means its not a level playing field as all other cars have to start off in first.

XXXX just went POP.

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Our Verdict

Porsche 718 Cayman

Can the best sports coupé of the decade absorb a contentious new engine?

Find an Autocar car review

Driven this week