According to Kahn Design, which has turned its attention to cars such as the Bentley Continental GT and Range Rover as well as the California's sister, the 599 GTB Fiorano: "This spectacular vehicle features the kind of treatment that makes Afzal Kahn’s designs a favourite amongst discerning customers and is principally used to showcase the latest modifications available from A. Kahn Design. Characteristic of cars given the thumbs of by Afzal Kahn – the A. Kahn Ferrari California is aimed at owners who desire a car which embodies everything the Kahn badge represents: sporty design and innovation with greater versatility. This vehicle, a personal favourite of Afzal Kahn’s, will satisfy even the most demanding of owners in terms of vehicle dynamics and driving pleasure.

Mechanically, the California seems to have been only lightly touched as Kahn Design quotes an unchanged 0-100 km/h time from the production standard of just less than 4 seconds, while using the sports car's 7-speed transmission, although the emissions it quotes of 310 g/km of CO2 is very slightly adrift of the stock California which is rated as 305.6 g/km.

The key under-the-skin changes are a new Kahn sports suspension system, while the Bradford based tuner said it has improved Ferrari's F1-Trac traction control which it claims: "has been further honed to suit the typical driving conditions expected for this vehicle." The changes continue with new forged 'Monza' wheels in matt black, size 9 x 21 at the front and 12 x 22 rear. Finally on the outside, Kahn promises "optimised aerodynamics".

The cockpit of the California has been retrimmed with higher quality materials although no interior photos have been released by Kahn Design which says that new accessories and equipment include seats, steering wheel, instrument panel and the infotainment system

Kahn Design adds in the press release for its new California project that: "Our cars offer tasteful exclusivity to those that enjoy the finer things in life. Kahn Design is for the individual who will not submit to a life of uniformity and who will only accept perfection. Dedicated to the creation of luxury bespoke vehicles, we redesign the ordered monotony of mass produced vehicles and rebuild them into individually tailored creations." One cannot be too sure many people would describe Ferrari's California as 'ordered monotony'.