Pimp my ride: How the 1% are customizing supercars

More super rich than ever before are ditching those luxury supercars you can buy off the forecourt and instead are customizing their rides to maintain that exclusive edge.

In the battle for exclusivity, high-end carmakers have tried offer bespoke services and ultra-luxe models.

Auto groups such as Ferrari are increasingly offering a personalized service when it comes to their top-of-the-range models. Earlier this month Rolls-Royce (RR.-GB) said in a statement that bespoke personalization was at its highest levels and the majority of customers asked for cars to with custom designs.

But the former CEO of Lotus told CNBC that the majority of carmakers cannot carry out the modifications that the one percent is after—and designing for the super rich will sometimes cost as much as the original.

"I believe car manufacturers are trying to go in this direction but are restricted by production processes, and cost implications and timing implications and obviously engineering implications," Dany Bahar, the founder of custom interior design company Ares Performance told CNBC.

The number of clients coming to soup up their autos with Ares has far outstripped Bahar's projections. He expected to service 25 custom cars in 2014, but instead managed 62, and this year the ex-Lotus boss said the company is likely to customize around 150 vehicles.

"If you are buying…a one million pound car, you would like to have your own taste in there. Sometimes just changing the leather or the stitching or the colour of the wood is just not enough," Bahar told CNBC in a TV interview.

The luxury car market is going strong. Rolls-Royce said that 2014 saw the highest sales in its 111-year history and other automakers are trying to tap the premium market. Mercedes announced the $190,000 Mercedes-Maybach S600 earlier this month, while U.S. carmaker Cadillac pledged $12 billion to tackle the luxury space.

Ferrari is even reducing the number of cars it delivers in order to bring further exclusivity to the brand.

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One analyst said that the growth of the luxury car market and the increasing number of vehicles sold has to some extent diluted the exclusivity of cars and is behind the push for more unique designs.

"The issue is that as more and more cars are being sold it is diluting the effect of the luxury brand," Winston Chesterfield, associate director at Ledbury Research, told CNBC by phone.

"The wealthy don't like buying something that is a quarter of a million pounds and see someone else with the same car."

Bahar said that the majority of customers won't ship their cars to his Modena factory, but instead normally buy brand new cars that are sent straight from the manufacturers to the workshop. Two thirds of his clientele coming from the Middle East and Russia.

And the most outrageous request he has ever received: A man asking for his girlfriend's jeans to be stitched onto his seat.