Looking for a manga...

Looking for a short shoujo manga.
Set in a trade school that the locals call 'Jail School', she's the only girl in the mechanics class.
Coming from a family of soldiers, although she's cute and bubbly when she gets angry it triggers a violent persona.
The manga starts with her trying to persuade the new transfer student (a guy) to join her team in building cars... something like that.
In the end they enter a contest with their finished product and win.

Help, really wanna find back this manga. ╥﹏╥