BMW M140i & M240i Tuning (B58)

The M140i and M240i are two of the best-value performance BMWs ever made — a 3.0-litre B58 straight-six petrol in a small, rear-drive body. They're also brilliant to tune.

Typical Stage 1 gains

On a custom Stage 1 map, an M140i or M240i typically climbs from around 340bhp to 420bhp, with a healthy torque increase and noticeably sharper response — all from software, no hardware needed. That's genuine supercar-worrying pace on the road.

Stage 2 and beyond

The B58 has famous headroom. With supporting hardware (a downpipe, intake and intercooler), Stage 2 unlocks bigger numbers again — the engine can safely take far more than standard boost when it's mapped properly on the dyno.

Don't forget the gearbox

Most are the ZF8 automatic, so xHP gearbox tuning is a natural pairing — firmer, faster shifts, launch control and a higher torque limit.

Want to know your car's figures? Check your gains or get a free quote.