hi could enyone please tell me if changing the gap settings on a spark plug is okay to do i want to change my spark plugs as my car is four years old now and they have never being changed i took my old ngk plugs out and they are the same as some bosch plugs that i have had a while the only difference being the gap settingi measured the gap and have now very carefully changed the gap settings on the bosch plugs to match the gap setting on old ngk plugs am i ok to do this thanks in advance michael