I am rounding 20,000 miles and am going to take a trip to Oregon in June. I know that it is not the manufactures recommended time to change yet but I like to change plugs in all my vehicles arend 20-30k. What plugs does everyone recomend? I have read that hemis do not like platinum? what brand and gap should I use.

 

i've always been a fan of champion...had bosch in my 4.7 and it ran like ****, dont wanna spend the money on NGK and i dont think they all that great for the hemi...if it was me, i'd just go with the stock champions

 

Consider keeping your stock factory plugs
but 'cut back' the ground electrode
and increase the gap to about 0.060
and sharpen all edges.

As you put the 16 plugs back in
'index' the gaps
so that the ground electrodes face one another
toward the center.
This allows the flame kernel to grow outward
un-obstructed.
======
from the FAQ:

On a 5.7Hemi, it is very probable that by re-arranging the stock 16 plugs to
their best position in other cylinders that is 'lucky for them' when they
tighten down, you could achieve indexing without buying more than
4-6 additional plugs at most....perhaps none at all.
My guess: Aim the dual plugs' ground posts each other (toward center of bore)
so the flame kernel can expand un-hindered outward. This leaves a small
spot in the center of the bore with a blocked flame path but it probably
won't matter because that spot is so turbulent anyway.

In the picture below the left hand sparkplug is the way I am talking about
but the right hand sparkplug needs to rotate clockwise another 90 degrees:



The factory stock ignition system that fires the dual plugs on the 5.7 is
apparently VERY good. Recently a few owners with high miles (68K and
108K) on original factory 5.7 sparkplugs have pulled them for inspection
and found these plugs are still firing with worn gaps as great as 0.075
inches.

This brings up the question of whether a 5.7 owner might want to pull his
plugs, sharpen all edges, then re-gap to 0.075 or more and do some MPG
testing to see if the dual larger sparks give enough 'fast burn' to improve
low rpm torque and fuel economy.

A DCx employee whose day job is running dynos reported that the stock
5.7 Hemi Ignition settings in the factory PCM is within 4 degrees of
'Mean Best Torque' at all throttle settings above 2000 rpm so it is not out
of reason that bigger gaps and sparkplug indexing could put you 'spot on'.

 

Thanks for the tips.

 

I went to the NGK V-Power's and I will stick with them. I used a simailar NGK plug in my Stealth R/T and loved them there. I would highly recommend them. I would also change the plug wires while you are in there. At 39k miles I actually managed to pick up a full MPG better gas mileage by changing plugs wires and installing an air intake.

 

ya stick with stock plugs, they are the best for the engine.

 

I would stick with the stock plugs. That is what the engine designer has determined to be what is best all around for that engine. Red

 

Chrysler has always recomended and used champion/mopar regular copper plugs, if you talk to the older guys that have dodge and chrysler they will tell you to put coppers in it, they all disagree with platinums

 

The problem with platinums I have read with the Hemi is that they platinum tip will come off into the cylinder. Stick with the stockers.

 

Good luck finding the Champion plugs. I checked with 6 local auto parts stores and they did not carry those plugs and I finally went with Autolite Platinum plugs that were in stock. At first, I was hesitant to get platinum plugs from what I have read on this board, but I have not regretted getting them. My own experience with them is excellent.
Where is everyone else finding the Champion plugs? The Dodge dealer? Just curious.