Tyre placard, on a mk2 van

Did they have one,as i want to run 15s on my van but the law is getting very hot on bigger wheels in newcastle.And the Bridgestone tyre place said,i will have no worries as escorts have no tyre placards on them and i could run 22s and not get in trouble.
Thanks
in advance
james

UNDERSTEER is when you hit the wall with the front of the car. OVERSTEER is when you hit the wall with the rear. HORSEPOWER is how fast you hit the wall. TORQUE is how far you take the wall with you.