The BMW 1M has a reputation of being one of the best performance vehicles to come from the German brand, at least ones in recent memory. There's always room for improvement, though. As an example, check out this car with a V8 engine swap from an E90-generation BMW M3.
The 1M used a twin-turbo 3.0-litre inline-six making 335 bhp (250 kilowatts) and 332 pound-feet (450 Newton-metres) during normal driving or 370 lb-ft (502 Nm) during a temporary overboost period. The only gearbox choice was a six-speed manual.
This car replaces that inline-six with the S65 4.0-litre V8 that makes 414 bhp (309 kW) and 295 lb-ft (400 Nm). While the torque output is a bit lower than the twin-turbo inline-six, the naturally aspirated mill is more easily adjustable for the driver. Careful use of the right foot can rotate the machine to the exact spot where it needs to be.
The host of this video notes that the 1M's short wheelbase and wide track make this machine fantastic on the track. The dimensions make driving the car feel like it's rotating around you when behind the wheel.
This isn't an authentic 1M but rather a conversion of a standard 1 Series coupe, so don't worry about modifying such a rare vehicle. The guy building them sells a complete car for around £30,000. There are upgrades like an Akrapovič exhaust, larger brakes, or Recaro seats to add to the price if you want the extra equipment.
This is a bargain compared to an authentic 1M, at least in the US where an example can easily fetch more than $70,000. According to the BMW M Registry, the company delivered just 983 of them in North American specification. There were also 4,155 examples in left-hand-drive European spec and 1,204 units in right-hand-drive Euro-spec.