Steve,
one other comment. If the car is on the original tyres they will be 6 years old. They may look good but at that age the compound hardens & that means you lose:-
1. Grip. When I bought my Roadster the tyrs were 8 years old. I managed a 180 degree skid of damp road with diesel.
2. the tyres provide a lot of the suspension function hence the low 22 psi pressure. As the walls harden the ride hardens.
The tyres should have an age code on them.
John
