Manhart MH4 900: rare BMW M4 CSL pushed to 922 hp and supercar territory

Manhart has had another go at the BMW M4 CSL and turned the rare coupe into the MH4 900. This time the focus isn’t on visual decoration but on what’s under the hood: 922 hp and 1,190 Nm.

The starting point is the M4 CSL, the lighter and meaner take on the standard M4 Coupe. In factory form the 3.0-litre inline-six S58 with twin turbos produces 550 hp and 650 Nm. Manhart’s work adds another 372 hp and 540 Nm on top of that, thanks to upgraded turbochargers and a new ECU map.

Manhart hasn’t shared exact acceleration figures. The stock BMW M4 CSL hits 100 km/h in 3.7 seconds, so the MH4 900 has every chance of dipping below three seconds, provided the tyres, gearbox and electronics can stomach the torque. In terms of output the coupe is now in supercar territory: 922 hp puts it well above the usual BMW M performance versions, even if it still falls short of the classic Bugatti Veyron and its 1,001 hp.

The exterior was made more aggressive too, but without rebuilding the whole body. The coupe got a carbon front splitter, a large diffuser, side skirt add-ons, new mirror casings, a small ducktail-style spoiler and multi-spoke concave wheels. The finish follows the usual Manhart playbook: black body with gold graphics.

Projects like this are rarely rational. The factory M4 CSL is valued for its balance, lower weight and collector rarity, while the Manhart MH4 900 turns it into a blunter instrument — fast, loud, spectacular and almost certainly demanding on the driver. On a track or a mountain road, the extra hundreds of horses can be as much a problem as an advantage.

The MH4 900 looks like tuning built around a single idea: showing how much is still hiding inside the S58. The real question is whether the rare CSL needs that kind of excess — or whether its value was always in the factory precision that BMW dialled in for reasons that went beyond the numbers.