The retrofit was quietly added to the company's website overnight, and is priced at US$10,000 ($13,000) before taxes and labour costs.
Two key changes occur as part of the upgrade. Firstly, the company installs smart fuses that monitor "current at the millisecond level and [are] pyro-actuated to cut power with extreme precision and certainty". Secondly, the main pack contractor is switched from steel to inconel, a space-grade alloy.
These changes allow throughput from the car's batteries to be raised from 1300 amps to 1500 amps.
After the upgrade is completed, the Model S P90D in Ludicrous Mode has a total system output of 397kW, up from the regular P90D's 345kW. With these extra horses on board, the upgraded Model S P90D is capable of completing the 0-60mph (0-97km/h) run in 2.8 seconds rather than 3.1 seconds of the bog standard P90D.
The Model X gets a similar power bump, which means that it is able to complete the 0-60mph dash in 3.2 seconds — a regular Model X P90D needs 3.8 seconds to hit to 60mph.
As well as hardware and performance upgrade, buyers who stump up the cash for the retrofit will also gain new P90D badges, complete with an underline to denote the fitment of Ludicrous Mode.
The retrofit option was previously offered to buyers down under who were awaiting delivery of the Model S P85D after the launch the newer P90D variant.
According to Heath Walker, a spokesman for Tesla, there are "no current plans" to offer the Ludicrous Mode retrofit in Australia.