I just change out my factory plugs for the 3923 as everyone here has suggested to cure the rough idle. But However I lost top end acceleration. Know Ido have KN filter and Flowmaster 50 exhaust. At 70mph with the stock plugs I bearly had to step on the gas and it would rocket to 80+. Now I I have to give it alot more gas and it slowly climbes. I know some of you will say just mash the pedal but I did not have to do that with the stock plugs in. anyone else experiance this. Im thinking of going back to the stock size, I would put the stock ones back in but my son had to much fun beating them into the ground.

 

I've read the 3923s for the 4.7 work well(mine do) I'm assuming yours is the 4.7.( I haven't heard much about them in any other motor.)


What did you gap them at?

 

I have the 4.7 and gapped at .40

 

I installed the 3923's as well and lost 1 MPG! I runs well though. I will be going back to factory plugs. I think the Chrysler Engineers chose the plug for a reason.

 

I know what you mean, This morning I noticed I lost accelaration across the board. Dont get me wrong it did smooth out the idle alittle, which is why I switched. I tow a 24ft travel trailer and an need all the power and accel I can get.

 

I have the AutoLite Iridium plugs in my 3.7 Dak and they seem to work just fine, I haven't noticed any problems with them, but I also don't notice any significant improvements, I just want them to last longer than the stock ones did.

 

I just picked up the 5224. Hopefully this clears up the issue

 

Awhile back I put the 3923's in my Dakota which has the 4.7 HO in it and I noticed a pick up in power and accelaration off the line. But I went to the 5224's because I lost MPG in town on the freeway my MPG went up a little but because I'm using my truck for my for work and do lots of stop & go driving I had to back the which.

 

I do alot of highway.

 

I will be going back to the factory plugs as well (but not the Champions). I have lost some MPG as well. I know I should be getting better than 17.5 on the hwy.