The Tesla [NSDQ:TSLA] Model S P100D is already the quickest car you can currently buy. Soon, it will be even quicker.

Earlier in November, CEO Elon Musk revealed that an “Easter egg” was coming that would unlock the car’s full performance. Yes, the 0-60 mph sprint in 2.5 seconds and quarter mile run in 10.78 seconds the P100D currently achieves was only a warm up.

Musk took to Twitter on Wednesday to reveal that the Easter egg is software optimization that will enable the electric sedan to now hit 60 mph in just 2.4 seconds and complete the quarter mile in 10.6 seconds. The software optimization will be beamed out to the cars in December.

This is impressive when you consider that the big family sedan accelerates quicker than cars like the McLaren P1 and Lamborghini Aventador. It’s even quicker than Rimac’s still-in-the-works Concept_One electric supercar, which has a 0-60 mph time of 2.6 seconds.

Incredibly, the software optimization will also apply to the Model X P100D, helping it shave 0.1 of a second off its own 0-60 mph and quarter mile times. It means the electric SUV’s 0-60 mph time will drop to just 2.8 seconds.