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Discussion Starter #1
For those of you that have upgraded your plug wires for your HEMI:

What kind? How much? and what mail order or auto shop did you get them at? I heard good results from the Shorty kits ... MSD makes a kit also.

I also purchased a set of 16 Platinum Champions... I haven't put em in yet... I'm thinking of returning them for copper plugs since there are quite a few reports of poor results from using platinum plugs in HEMI engines all over the web.
 

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Discussion Starter #3
Ummm.... Maybe on the 4.7L ... But on the 5.7L HEMI, there are 16 plugs (2 per cylinder). There are 8 ignition modules, each one controls one plug directly underneath the module AND another plug (via high current wire) on the other side of the engine for exhaust detonation.

I did some more reading up on the Taylor shorty wires ... and there are reports of decrease in performance due to the change in spark order. Hmmmm... more research needed.
 

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I work for Honeywell - Autolite and I'm planning on putting XP5263 in. I have an '02 Wrangler that started having poor gas mileage and I put some XP's in it and my mileage jumped from 15 to 21. I know it's a different engine, but it Champion plugs are not good.
 

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Chipster009 said:
... and there are reports of decrease in performance due to the change in spark order. Hmmmm... more research needed.
Yeah, I can see where you could lose performance if you changed the spark order.....
 

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Discussion Starter #6
Just an update....

4.7commander was right. The newer HEMI's no longer have the high-current wires going accross the engine. I swapped my plugs last night on my 2006 5.7L Commander. There is one ignition module per cylinder firing both intake and exhaust plugs. 2 boots come straight out of the module into the cylinder cavity/contacting the plugs.

It took a little over an hour to change all 16 plugs. The most difficult part was dealing with the cylinder driver's side second closest to the front. There's a fluid reservoir and fuse block/plug assembly that got in the way. Other than that... it just took patience to loosen 16 ignition module mount bolts and 16 old plugs .. then gap the 16 new NGK V-power coppers to 0.44" then install plugs and re-install modules.

At 37k, the original Champion copper plugs didn't look bad at all... color was good (light orange color, no oil deposits, electrode shape was still normal). There was a lot of contact grease in the boots.. but that's fine.. I just transferred some to the new plugs.

The idle is a bit smoother. The acceleration seems to be a little bit better. I took a brief test drive on damp Southern CA roads last night... and the HEMI performed nicely :)
 

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Chipster009 said:
Just an update....
Keep the updates coming...! I'd like to know if your mileage changes at all.

Are the new plugs copper or platinums?
 

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lekmedm said:
Are the new plugs copper or platinums?
Read his post again. Doh !

It took a little over an hour to change all 16 plugs. The most difficult part was dealing with the cylinder driver's side second closest to the front. There's a fluid reservoir and fuse block/plug assembly that got in the way. Other than that... it just took patience to loosen 16 ignition module mount bolts and 16 old plugs .. then gap the 16 new NGK V-power coppers to 0.44" then install plugs and re-install modules.
 

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The Taylor shorty wires work great. Ive used them twice. In my 04 Hemi Ram and in my Intrepid. They work great and as far as plugs the NGK's work great also, but the only thing bout them is the life of them. Ive heard here and there that they dont last as long as the standard Champions that come in our hemis from the factory. Will still use them but will keep an eye on them every 10,000 miles.
 
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