When should i change my plugs?
 

Just wondering the above, they are ngk iridium 7's, they were fitted about 2 1/2-3 years ago and have done approx 5-6k, my cars a 2.5wrx and i'm running 1.5bar, what do you think? edit to add, the car is running fine btw:)

Should be fit for about 20k I would of though. Mines the same car wth 10k on it from new and its 3 year old now so the plugs will be there for another 3 years