Tires: tire size, chevy beretta, pontiac grand prix

Question
I have a 97 Pontiac Grand Prix,with some badly worn out tires 225/60/R16. I do have brand new tires from my old car,a 90 Chevy Beretta 205/55R16 .COULD I MOUNT THIS 205/55R16on my Grand Prix ?. If not please explian.My brothers say yes,My machanics say no,That it could ruin my computer.Please advice,as im short on cash ..THANKS FOR YOUR TIME IN ADVANCE  

Answer
Lorenzo,

There are 3 reasons why this is a bad idea.

1)  The tires are 3 sizes too small.  That means that the tires are likely to get overloaded with even a couple of people on board.

2)  The tires are 7% different in diameter.  That means the ABS system is going to think the tires are not performing properly when they are!

3)  The tires are old.  IMHO anything older than 10 years needs to be removed from service.  Anything older than 6 years, should be considered for removal.

Hope this helps.