Tires: different size tires on a fwd drive car, size tires, rear tires

Question
Hi-bought a used chev lumina (car not van) as a second vehicle. Manufacturers spec for tires is  195/75/14 all around. The tires (brand new) currently on the front are 195/70/14s. The rear tires need replacing. I already have a pair of new 205/75/14s and i was going to put them on the rear--but was wondering if they should go on the front instead--or is there a problem with mixing the sizes regardless of front to back configuration?  

Answer
John,

You have a real problem:

First, it's not a good idea to have different size tires front to rear if your car came with the same size all around.  But if you are going to put larger tires on, they ought to go on the rear so the car has more understeer.

However, the front tires are a size too small for your car and shouldn't be on the car at all, but it would be worse to have them on the front.

My recommendation is to inflate the small front tires to 35 psi and the larger rear tires to 30 psi.  But at your earliest opportunity, get 4 tires of the same size, as the current configuration is a bit problematic.

Hope this helps.