Turbo Engine is a Titan Kit in Titanfall 2. It allows 1 extra dash on your Titan except for Scorch and Legion. When equipped, it will make Titans resemble their Titanfall chassis more. For example, the Atlas-class Titan had two dashes in the first game, but the equivalents Ion and Tone only have one by default.
Atlas-Class Titans such as Ion and Tone, alongside Monarch will have 2 dashes instead of 1 with Turbo Engine Equipped.
Ogre-Class Titans such as Scorch and Legion will have shorter cooldown with Turbo Engine Equipped instead of an extra dash.
Stryder-Class Titans such as Ronin and Northstar will have 3 dashes instead of 2 with Turbo Equipped. However, the addition of Phase Dash means that Ronin will, in effect, have four dashes as opposed to three.