2023 Mercedes-AMG SL 43 has electric-boosted turbo for zero lag

Most car manufacturers use motorsports to develop new technologies that can be passed on to their road cars, and Mercedes-AMG is no exception.

Their successful Formula One program resulted in the One hypercar, which uses the V6 hybrid engine straight out of their F1 car. And now, another F1-derived technology has been passed on to their high-performance road car.

Behold, the 2023 Mercedes-AMG SL 43; the entry-level version of the carmaker's SL-class roadster lineup.

On the outside, the SL 43 looks similar to its SL 55 and SL 63 siblings except for a few differences. There's a small change to the vents on the front and rear fascia, and the exhaust tips are oval-shaped instead of the usual square finishers. The car also rolls on a unique set of 19-inch wheels.

Other variants of the SL-class are typically powered by a twin-turbo V8. But for the SL 43, it gets a 2.0-liter, four-cylinder single turbo engine that produces 381 PS and 480 Nm of torque. In typical AMG fashion, the engine is not a normal turbo-four. This is the first-ever production engine to utilize an electric exhaust gas turbocharger.

That's right. The car's got an MGU-H unit like a Formula One car. The turbocharger is assisted by a 48-volt electrical system that feeds the belt-driven starter-generator. This means the electric motor spins up the turbine at low engine speeds until there is enough exhaust pressure to spool it up like a regular turbo. In other words, turbo lag is basically eliminated, and engine response should be greatly improved.

Furthermore, the electric motor also provides an additional 14 hp, which technically makes the SL 43 a mild hybrid. The engine is mated to a 9-speed AMG speedshift multi-clutch transmission that transfers its power to the roadster's rear wheels.

Mercedes says the SL 43 can reach 100 km/h from a standstill in just 4.9 seconds, with a top speed of 275 km/h.

Now that electric turbos have made their way to road cars, we could soon wave the dreaded turbo lag goodbye.