According to my B210 factory manual, the wagon is fitted with a H150 diferential with a tooth count of 35/9 which equates to a ratio of 3.889 to 1. Just round it off to 3.9 to 1.

I can't help it, but every time i read your "signature" i think, I know what's priceless. That'll be the look on your face when the Judge says " Ninety days, & vehicle forfeited. [confiscated] That's when the cop will have a wry grin, then walk outside chuckling.
Now, i don't know if they can actually take the car, but Judges have a sense of humor too.