hi, ive just changed my wifes wheels from 15inh to 16,s of a mondeo, on her escort gti, shes convinced the tyre pressures are 28 psi all round, mine are at 31 psi, which i think is right, but she wont budge, can someone tell me whats the recommened tyre pressure for 16 inh alloy wheels, so she can see for herself. thanks.