the torque specs when changing the spark plugs

Dear mccord88-- Your spark plugs are easy to change and you are right to be careful concerning the torque applied when tightening them back in. If you buy your plugs at a responsible retailer, they will give you the required torque specs. Otherwise go to the following site for a chart which will answer your question for both the 2003 Toyota Celica and the 1999 Mazda MX5. Go to-- http://autozone.com/az/cds/en_us/0900823d/80/04/d0/00/0900823d8004d000/repairInfoPages.htm. Good luck from Bovan.

What is the torque spec. For spark plugs on a 1999 MX 5

Depends on the spark plug