Sharps is correct.

Straight out of the service manual. 2nd, all these motors were never built to run platinum plugs dude.

CAUTION: The 4.7L V–8 engine is equipped with
copper core ground electrode spark plugs. They
must be replaced with the same type/number spark
plug as the original. If another spark plug is substituted,
pre-ignition will result.


BTW<------ Same goes for the 3.9L, 5.2L, and 5.9L motors.

 

thanks hydra, for future refrence would it be better to just get an good port job done on them or is it cheaper to just get new, high quality aluminum heads? Is anything along with the heads that should be replaced to corrospond for the higher flow numbers? So an no on bigger cams?

 

The OEM cams should be fine to run ported heads. Me personally, I would buy new ported heads and rebuild the motor with a punch of about .002 over. And remember to get new timing components and the whole enchilada.


As for exhaust, on the 4.7L you have a CAT for each cylinder so our good, however I would run shorty headers. Second you might want to change to a larger "Y" pipe and 1/2 inch larger single pipe from the CAT back with a good Magnaflow muffler if you feel you are choking the motor.

 

WRONG the 4.7 has ONE cat on EACH SIDE, and ONE after the Y pipe, so 3 cats, the ones coming off each bank of cylinders are the one with the o2 sensors on them

 

My bad, I meant one for each side (manifold) of the engine. There should be one CAT on each side and they are called MINI CATS. 1 - 02 sensor before and one after on each side for a total of 4 02 sensors.

Why in the heck would there be a third CAT after the exhaust and "Y" and after has been through a CAT unless a California model?

Remember there is the following for both 5.2L,3.9L, 4.7L and 5.9L motors unless California.

1/1
1/2

Here is the rest of the 4.7L:

2/1
2/2


For instance, on my truck there is a CAT on each side with a 02 sensor before, then out of the CAT's it goes into a "Y" pipe with a single 02 sensor to monitor the output.

Then the 3 series like mine and also California 5.2L, 3.9L and 5.9L:

1/3
2/3
3/3

 

maybe my truck meets california emissions, but i coulda sworn there was 3 cats, and a muffler in there (no sensors on the third cat)

 

Thanks, so theres basically no way to get "Respectable" power out of the motor without porting heads or spending several grand?

also this WILL probaly sound stupid and im not sure if this would even slightly work, but what about topping the car off with something such as holley stealth ram, accel super ram, tuned port injection, ETC.? Or is there anything made for mopars that can compare (compare i mean by focusing on low end torque as not so much high end power)?

I realize tuning would be needed to done but would the intake swap be any more diffrent then if you were to be doing the same swap on an GM engine?

I'll probaly end up never doing much to the 4.7 but someday in my life i would like to do something along the lines of an 5.7 hemi swap

also that reminds me, what about swapping intake to the 4.7 H.O. version? as far as i know for the H.O motors its just an diffrent intake and if i remember right its about an 40hp diffrent, seems extravagent but hey, cant an man dream?

 

if i remember right a guy posted his hemi swap in a dak in the dak forum sec. and just because it comes from the factory that way doesn't always mean its the best, i.e recalls and constant updates in parts. last time i checked copper core plugs in a high energy ignition system causes premature electrode wear, and didn't you say the factory designed the heads poorly so maybe they put in cheap plugs to save a buck too. 8 bucks a set compared to 36 to 50 a set changes your bottom line quiet a bit when you put together a few hundred thousand engines. i have never had problems with double plats or iridium plugs in fact most manufactures have changed to iridium plugs as a parts replacement. i'm not trying to start a knowlege battle just my thoughts.

 

if dodge thought the platinum plugs were the best for the engine they would have thrown them in, and then passed the cost on to you (or me), the consumer, they dont care. trust me when i say that they designed these engines to run on copper core plugs, and MANY people have reported alot of problem with platinum plugs, especially the ones which have mulitple tips for 'better spark' (its a load of bull****, the tip closest to the ground is the one that sparks, the others are just for show)

 

reason i say hemi is as it seems its pretty much the only motor thats made now that makes respectable power. So know one got thoughts on HSR or TPI?