Get bonus parts To earn bonus - Silent Line: Armored Core
Get bonus parts
To earn bonus parts, get an A or S on any mission
Get defeated AC emblems
To get Emblems from defeated ACs, press START+SELECT when the victory
To boost faster press both L3 and R3. You should boost forward at twice the normal speed until you run into something.
However, you can not stop until you run into a wall or other object, so there is risk of using all your boost.