Reply to thread

Message: <blockquote data-quote="zombiekiller" data-source="post: 1274411" data-attributes="member: 25186">it doesn't "need" them. depending on the particular motor, these can sometimes smooth out idle and hesitation. If you're experiencing any of the following: detonation, pre-ignition, or power loss; colder plugs could alleviate it. I am surprised that more "gear heads" are not familiar with using different spark plugs to better tune their engine.in all reality, for every 75-100 HP that is added to a motor, you'll generally want to go one step colder. ( be wary though, not all spark plug MFGs rate their temp ranges the same). the leaner your AFR is, the colder the plug should be ( in general). just remember colder heat range = faster heat transfer. The fact that the tuners are saying that there is no need to change plugs leads me to believe that the AFRs on most tunes are fatter. ( and that they are being cautious with thier tunes.) If you find that your motor is adding or removing lots of timing (like more than 3 degrees + or - during normal, steady throttle operation) this could perhaps be a solution that Ford certainly isn't going to offer you.</blockquote>