..I agree with NH...you should already know and be running NGK 4306's to stay on the safer side...

 

I have stuck with the OEM coppers on two Hemi's, zero problem, $30, why use anything else?

 

because some people mod and the oem's won't cut it...but for the 80 percent that don't mod, yes, stick to the oem coppers..

 

ive used E3s on two differen Hemi's and have not had any problems. Compression is still good so no valves have been burned or warped. They seemed to improve performance slightly, because the trucks have better throttle responce.

 

The only time that a set of spark plugs will give an 8hp gain on a stock to mildly modified N/A engine is when the old ones are worn slick out. I personally run the copper NGK V-Power plugs in my Ram and Mustang and have never had an issue. I will put them in my Caliber and CG when the time comes.

Mopar using Bosch? I'll never use those crappy plugs again after losing a motor due to a platinum electrode falling out and wedging between the piston and cylinder wall.

 

The 08+ redesigned 4.7L's with the 16 plugs use Bosch plugs OE. Regulars on the uppers( 30K )and Iridiums on the lowers( 102K ).

 

Well on a HEMI Ram for example it is very difficult to change the plugs and there are 16 of them. It is also very expensive for those who pay to have them changed at approx $250 labor for the average charge.

Many people upgrade to a premium plug( Platinum or Iridium )to increase the service life of the plug from 30K running standard copper cores to 100K. They can get 3X's the service life out of one plug vs 3 sets of coppers. When you pay to have them done at $250 a pop it is a lot cheaper using premium plugs and getting that 100K time frame.

Take a minute and look at the numbers. I will use just some approx numbers. It isn't 100% accurate but it is about what it costs...

COPPER:
16 plugs X $2.25 = $36.00
Labor = $250.00
Total for 30K = $286.00
Total for 100K = $286.00 X 3.33 = $952.38

PREMIUM:
16 plugs X $6.50 = $104.00
Labor = $286.00
Total for 100K = $390.00

Savings running premium plugs 100K vs changing copper cores 3.33 times @ 30K intervals = $562.38

That is a pretty significant savings over that 100K when you have it done at a shop. If you do the plug swaps yourself it is still less money over that 100K plus you don't have the banged up knuckles and aggravation of doing it.

$104.00 for 16 premium plugs over 100K
$119.88 for 16 copper core plugs X 3.33 over 100k( 30K intervals )

So there is a benefit to the premium plugs at least based on $$$. To many people that is appealing.

 

I pulled stock Champions out of mine and put back in the same.

 

WOW!!! I would change them all day long for $250 labor. My first time only took me about 1hr or so.

The 08 brochure says that the 08 4.7 uses platinum plugs on the bottom, not iridiums. But, who knows.

Also, since copper is the better conductor of electricity, you get a better spark from a copper plug. Platinum last longer but the spark isn't as hot.

 

E3 work just fine in my 4.7L motor and my ATVs and Mowers, Never fouled one yet, main reason I went to them was they do not foul or need replaced as often as the stock plugs. I have had more issues with Champion plugs in the past blowing the ceramic out of the metal part than miss fires with any other plug on the market.
It is well known that Autolites (one of the cheaper plugs) are the easiest to make a spark with that is why they used to be the plug of choice for VW bugs and older ford motors they both had weak coil setups. From all the complaints on doing Hemi plugs I would put Iridium in those motors and foget it. Next time it was time for plugs just trade it off..