Although an accurate overall guide to tyre inflation pressure is not possible, it is possible to give a basic overview of optimal tyre pressure based on vehicle weight (assuming the car is front engine, rear wheel drive). There are a number of factors which will alter the accuracy of the table below.
For example, front-wheel drive cars, which place a much higher load on the front tyres, require a higher inflation pressure. Vehicles with independent rear suspension (IRS) can often run lower tyre pressures than non-IRS cars because they're able to control camber settings more closely.
As previously mentioned, the above table is intended for use only as a rough guide. Optimal inflation pressures differ from one car to another (even amongst FR vehicles), based on such factors as camber, IRS, and suspension type.
Optimal pressures are often best determined by on-track performance and individual driver preference. Additionally, some tyre manufacturers (such as Hoosier) recommend that their tyres be inflated at higher than normal pressures because they're more suited to such conditions.