Tires: New Tires, nissan 200sx, 1995 nissan 200sx

Question
I own a 1995 nissan 200sx SE-R and I reccently noticed a lot of cracking in the rubber on my tires. My dad said it was from me driving around with overinflated tires. The back two tires seem to be in ok shape, but the front two have a lot of cracking and some tread separation on the outter sides of the tires. My normal tire size is P195 55 R15 but I am having a hard time finding tires that match exactly and are within my price range. The closest matches that I have found so far are P195 60 R15 and P195 50 R15. My question is canI buy tires with a higher or lower aspect ratio and mix it in with my old ones? Or should I buy tires with the recommended 55 aspect ratio? Also since I'll probably be keeping the two back tires should I have them moved to the front and put on the new ones on the back?
Thank you,
Tyler

Answer
Tyler,

Cracking is usually the result of tires that are underinflated or are getting old.  Cracking is part of the natural degradation all organic materials experience.

You can go larger in size, which means going UP in aspect ratio.  

Rule of thumb - To find a comparable size, go wider by 10mm and lower in aspect ratio by 5.

So a P195/55R15 has equivalent sizes - 185/60R15, 205/50R15.

But be sure to check the rim width to see if the new tire would proper fit.

Your vehicle came with 6" wheels so both of those sizes work.

I'd recommend you use the 205/50R15.  There ought to be plenty of options there.  This also is compatible to your plan of using the new tires on the rear.  And use the same inflation pressure as on the placard - 29 / 33

Personally I like to use 3 to 5 psi higher than the placard.  I get better wear, better fuel economy, better wet traction, better snow traction, better steering crispness, better tire durability, and only give up a bit of ride harshness.

Hope this helps.