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are the bosch platinum +4 not suppose to be good? I havent had any problems with them? They are the MOPAR upgrade? I think I picked them up at napa for like $6 a piece......
Yes...they are good. You are correct in the fact that they are the Mopar Performance upgrade plug as well. I run them in both of my 4.0L Jeeps as well as in my 2002 Ram 4.7L.


I have come across some 4.0L engines that don't like Platinums at all for some reason, but that has only been maybe two or three times in 20 years. ;)

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Not always more performance...but definitely longer life and sometimes a "little" better MPG.


I get the best mileage and a better idle with the Champion copper cores. I think the heat range is the most important. The stocker 4.0s seem to run best w. the RC12s, but they were too hot for my stroker and I dropped down two heat ranges to RC10s and their color now is spot on.

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