When Tesla first introduced the Model S P90D with Ludicrous Mode, P85D owners no longer had the top-of-the-line performance version of the electric sedan. To make it up to owners, Tesla eventually offered a discounted Ludicrous Mode retrofit for the P85D (priced at $5,000, rather than the $10,000 upgrade in the P90D). The Ludicrous Mode upgrade for the P90D was only available when configuring the vehicle - you snooze, you lose. Not anymore, though, as Tesla is now extending the option of a Ludicrous Mode retrofit to P90D owners who passed on the upgrade when originally ordering the car.