B-Spec Mode is the secondary and AI-controlled part of the later Gran Turismo games. First appearing in Gran Turismo 4, it revolves around the player using the gamepad or steering wheel to instruct an AI-controlled driver to race on their behalf, a feature not seen in the earlier games.
The player can select from 5 different paces, or speeds, and can instruct the AI driver to overtake the car ahead, or pit in if new tyres or more fuel is needed. The race can also be sped up by a factor of 2 or 3, making longer races, such as the Grand Valley 300km endurance event, able to be completed in a much shorter period of time.
There are also 2 view modes in B-Spec: race view, which displays the ongoing event via replay cameras, and monitor view, which displays a new screen. On this screen, players will see a map of the course and the positions of both their AI driver and the opponent cars, labeled as letters from "A" through "E", where the player's car will always be "F". The same instructions that can be accessed on the race view screen can also be seen here, as well as the fast-forward controls, and a live-view diagram along the bottom that will show the distance between each car in metres.
Main article: B-Spec Points
B-Spec Points are earned based on the player vehicle's performance compared to the opponents'. They are used to increase the AI driver's skill in specific areas; machine skill, course skill, and battle skill. They are otherwise not redeemable for anything; prize cars or otherwise.