Its amazing that the tyre fitters will pump any old PSI into the tyre on the sealing of the tyre on the press but dont check the pressures with the vehicle on the ground.
Although tyre pressure should be checked at least once a month very many people are driving around with incorrect PSI.
An MX5 is very critical to tyre pressure, more so than the average family shopping hack where you probably wont notice the difference much. However, the tyre pressures are so important whatever the vehicle.
Over inflation on newly fitted tyres is very common but shouldn`t be.
Checkem. It makes sense