Originally Posted by Oceania94

Hi everybody.
Quick question relating to spark plugs. My plugs are right on service interval and I have noticed the owners manual is at odds with what everybody else is running and what NGK recommends.
Owners Manual states NGK PFR 5-11 while NGK and a lot of other places seem to suggest NGK IFR6D10.
Just wondering if anyone has any advice before I shell out for plugs my car is N/A I'm assuming that the SRT and N/A run different plugs. I did notice the PFR plugs are not the correct gap however any issue with changing from a 5 heat range to 6 with the IFR ?