Local BMW 135i and 335i owners can now have a factory approved tuning package fitted to their N54 engined cars, which should irk M3 owners no end. Liberating the extra power is an engine management upgrade and air intake modification. The performance power kit is not a simple backyard chipping job, though. It includes an additional radiator fronted by a high-flow fan and additional air intakes for optimal cooling. The sum total is a power boost from 225kW to 240kW and 30Nm of extra torque – now peaking at 430Nm. If owners install the kit in an automatic 335i or 135i the torque peak is bumped up by another 20Nm to 450Nm. Outputs are in line with the new 740i, which uses the latest version of the award winning, 3-litre, twin-turbo straight-six. BMW claims a performance power kit fitted 335i should sprint from 0-100km/h in 5.4 seconds dead, a gain of 0.2 seconds over the standard car.A chrome-plated dual exhaust is part of the package, and should shore up gas expelling acoustics and durability.Chrome plated dual exhaust nice, but look a bit asymmetrical jutting out from under the bumper all on one side...Suspension, brakes, steering wheels... Beyond the N54 engine upgrades the BMW performance kit can be optioned to include suspension, aerodynamic and cabin enhancements.Performance kit equipped 135i and 335i models will ride lower (by 25mm) than their stock siblings thanks to new yellow springs from BMW’s motorsport division, which are 48% stiffer.Aerodynamically, an integrated kidney surround and new front apron dovetail with the carbon-fibre aft spoiler and diffuser treatment, ensuring outstanding high speed stability. Front axle torsional rigidity improves (negligibly) thanks to a strut brace.Performance brakes, boasting increased rotor size (430mm versus 338mm) and six-piston calliper actuation, keep the additional power in check. Seats are very much love/hate items aesthetically. Should do a fine job when those lateral forces start loading up. Cabin appointments from the Performance kit catalogue tally new, sculptured, seats and an ergonomically enhanced three-spoke steering wheel which looks as if it was taken off an E46 M3.Those BMW owners who embrace the joys of technology with abandon will be heartened by additional LED displays which illuminate a host of crucial technical information - like shift points as well as transverse and longitudinal acceleration.Excluding labour, the power upgrade kit is R24 265, whilst all the other trinkets are available on request from dealers. Warranty and motorplan contracts are, naturally, unaffected by the BMW performance kit.