Separate Spark Plug Thread for the 4.7's
 

Well, I went all the way through the "What are you guys using for spark plugs" thread and never saw a single mention of the Ram 4.7.

Okay, so what's the "plug of choice" for the 4.7?

Thanks!

Arn't you the guy who claims he puts on 5K a year? Check back in just under 10 years when you have to replace the first 8 :)

Upper Bank — FR8TE2 (Gap 0.039 in [.99 mm])
Lower Bank — FR8T1332(Gap 0.051 in [1.30 mm])

Oh I'm the guy all right. Was merely curious for my own info... :)

Thanks!!

I am past due for changing the upper bank of plugs in my 2010 4.7L and have been trying to decide what do do plug wise. I have some minor mods and planning more, will end up at about 375-400hp (65-90hp over stock). I'm wanting to go to a plug that is one heat range colder, does anyone know what plugs I should use? I'd like to keep the cheaper plugs in the top bank (I assume these are copper...?) and keep the iridiums in the lower bank but just go to the next heat range colder.

Also, should the gap be changed at all? I don't understand why there's such a difference in gap between the upper and lower banks. Is it because of the material? If so, would using the iridiums in the upper bank be an improvement? And lastly, if I went to a colder heat range in the upper bank now, then did the lower bank later, would that have any negative effects until I change out the lowers?

Sorry so many questions lol, I find that these engines with 2 plugs per cylinder and different plugs at that can be confusing...

From the research I did when you have more timing advance, higher octane fuel, and more power output (I have all of these) you should/can go to a colder plug. I just want to make sure I pick the right plugs the first time as they are expensive for so many of them...