Spark plug change interval?

[MOPAR78]

Those last 3 on the drivers side really suck. I've always changed mine out at about 100,000 miles with the exception of the last time. I had over 250,000 miles on them and she was still running smooth. I was surprised at the condition of them.

 

[HEMIMANN]

Those last 3 on the drivers side really suck. I've always changed mine out at about 100,000 miles with the exception of the last time. I had over 250,000 miles on them and she was still running smooth. I was surprised at the condition of them.

what type were they? stock iridium?

 

[MOPAR78]

what type were they? stock iridium?

Yes. I did not know until I pulled them out. By coincidence I had already purchased iridium for the change.

 

[HEMIMANN]

Well, there's some user proof iridium plating lasts longer than plating plating. Then again, we already knew that.

Too bad spark quality suffers.

 

[Wild one]

Those last 3 on the drivers side really suck. I've always changed mine out at about 100,000 miles with the exception of the last time. I had over 250,000 miles on them and she was still running smooth. I was surprised at the condition of them.

I don't mind the drivers side as much as the back 2 cylinders under the wire harness and heater hoses on the pass side,lol.Even with both the harness and hoses unclipped,they're still a ***** to get the coils off of,aarrgghh,only time i wish i had a body lift is when i'm doing them back passenger side cylinders,lol.Do you have the Gearwrench 5/8" X 6" swivel socket Mopar,if not it's well worth having,makes doing the plugs a little nicer.

 

[Wild one]

Well, there's some user proof iridium plating lasts longer than plating plating. Then again, we already knew that.

Too bad spark quality suffers.

On a stock engine,with the factory coil on plug ignition,there isn't enough measurable differance in fuel milege or power to be noticed,and in that case the average owner wants the least amount of maintence as possible.If your on high boost or nitrous,then the good old copper plugs are a worth while investment.But the guys in that situation usually change the plugs fairly often. I run good ole cheap Denso 3381 copper plugs in my toy,and they get changed every season,sometimes even twice a season,and our season up here is maybe 8 months long,on a good year,lol. As soon as they loose their sharp edges on the electrode and ground strap,they get swapped,lol

 

[HEMIMANN]

On a stock engine,with the factory coil on plug ignition,there isn't enough measurable differance in fuel milege or power to be noticed,and in that case the average owner wants the least amount of maintence as possible.If your on high boost or nitrous,then the good old copper plugs are a worth while investment.But the guys in that situation usually change the plugs fairly often. I run good ole cheap Denso 3381 copper plugs in my toy,and they get changed every season,sometimes even twice a season,and our season up here is maybe 8 months long,on a good year,lol. As soon as they loose their sharp edges on the electrode and ground strap,they get swapped,lol

Yes - I'm thinking more about minimal deposits, etc., from incomplete combustion. Go to NGK site and look at high speed pics of combustion fronts.

 

[crackerjack1957]

I run good ole cheap Denso 3381 copper plugs in my toy,and they get changed every season,sometimes even twice a season,and our season up here is maybe 8 months long,on a good year,lol. As soon as they loose their sharp edges on the electrode and ground strap,they get swapped,lol

Holy knuckle buster.......that toy gets more loving care than the wife.........LoL

 

[Wild one]

Yes - I'm thinking more about minimal deposits, etc., from incomplete combustion. Go to NGK site and look at high speed pics of combustion fronts.

Pull the heads off the average Hemi,and get back to me about combustion deposits,lol. Coil on plug ignitions are differant then the old style single coils of years ago,they have enough coil saturation time to produce enough spark on a bigger plug gap to have as close to a complete burn as possible.NGK uses marketing to their advantage,if i remember right they're also the ones telling you not to use an anti-seaze on a plug as it doesn't properly ground,and that we know doesn't happen,even old style ignitions will still fire an anti seaze soaked plug lol. A copper plug only shines when it's new and still has it's sharp edges on both the electrode and ground strap.Spark leaps from one sharp edge to the the other sharp edge,as soon as the sharp edges are gone,the plug starts to become less efficient and requires more coil saturation to create a spark.That's why the irridiums are a better plug in the long run for the average owner.Next time you have a new set of plugs in hand,look closely at the inside of the ground strap,you'll notice it's not flat,it's cone shaped to create two sharp edges for the spark to leap to.Copper plugs only shine when they're new,lol

 

[Wild one]

Holy knuckle buster.......that toy gets more loving care than the wife.........LoL

She'd probably agree,lol

 

[MOPAR78]

I don't mind the drivers side as much as the back 2 cylinders under the wire harness and heater hoses on the pass side,lol.Even with both the harness and hoses unclipped,they're still a ***** to get the coils off of,aarrgghh,only time i wish i had a body lift is when i'm doing them back passenger side cylinders,lol.Do you have the Gearwrench 5/8" X 6" swivel socket Mopar,if not it's well worth having,makes doing the plugs a little nicer.

No I do not have the Gearwrench 5/8" X 6" swivel socket. I'll check into that. Thanks!

 

[Different Drummer]

C5A on the plug threads for me.

 

[HEMIMANN]

Pull the heads off the average Hemi,and get back to me about combustion deposits,lol. Coil on plug ignitions are differant then the old style single coils of years ago,they have enough coil saturation time to produce enough spark on a bigger plug gap to have as close to a complete burn as possible.NGK uses marketing to their advantage,if i remember right they're also the ones telling you not to use an anti-seaze on a plug as it doesn't properly ground,and that we know doesn't happen,even old style ignitions will still fire an anti seaze soaked plug lol. A copper plug only shines when it's new and still has it's sharp edges on both the electrode and ground strap.Spark leaps from one sharp edge to the the other sharp edge,as soon as the sharp edges are gone,the plug starts to become less efficient and requires more coil saturation to create a spark.That's why the irridiums are a better plug in the long run for the average owner.Next time you have a new set of plugs in hand,look closely at the inside of the ground strap,you'll notice it's not flat,it's cone shaped to create two sharp edges for the spark to leap to.Copper plugs only shine when they're new,lol

Ok, then why are they pushing ruthenium as the latest wonder-plating?

 

[Wild one]

Ok, then why are they pushing ruthenium as the latest wonder-plating?

Supposedly it has twice the life expectancy of irriridium,but so far there's still not much info floating around about them.NGK seems to be the push behind them.When you dig up some info on them,post it,as there isn't much on them yet

 

[HEMIMANN]

Supposedly it has twice the life expectancy of irriridium,but so far there's still not much info floating around about them.NGK seems to be the push behind them.When you dig up some info on them,post it,as there isn't much on them yet

Only what I read on NGK site. Longest life but near as good spark as nickel-plated copper. For triple the price. But - the key another member reminded me is these ECM's are set for what spark plug characteristics the truck was built with - not aftermarket changes.

Someone would need to custom tune for ruthenium plug resistance.

 

[Wild one]

Only what I read on NGK site. Longest life but near as good spark as nickel-plated copper. For triple the price. But - the key another member reminded me is these ECM's are set for what spark plug characteristics the truck was built with - not aftermarket changes.

Someone would need to custom tune for ruthenium plug resistance.

I doubt there would be enough of a timing increase to need a tune to retard the timing. I can't see the timing increase being anymore then running a set of stock irriridiums gapped at say .036" instead of the normal called for gap of .041". They might increase coil life expectancy,but that one would be hard to document,as i doubt there'd be enough of an increase in coil life that'd be measurable,or prove-able to a spark plug. The only real advantage that i've gathered up is the life expectancy of them compared to an irriridium plug,the resistance differance isn't enough to affect the average stock truck or it's timing advance in the pcm

 

[Docwagon1776]

All the old ones are out. About done putting the new ones in on the driver's side, then I'll put the coil packs back on. Break time.

 

[HEMIMANN]

All the old ones are out. About done putting the new ones in on the driver's side, then I'll put the coil packs back on. Break time.

How long did it take? How many miles?

 

[Docwagon1776]

How long did it take? How many miles?

I didn't time myself, but a little under 2 hours. Not quite 67k mile. They were done at 33k.

With the gear wrench doo-dad it wasn't that hard at all. Much easier then what I anticipated from the way people talked about it. 10mm stubby helps on the hard to reach coils.

 

[HEMIMANN]

I didn't time myself, but a little under 2 hours. Not quite 67k mile. They were done at 33k.

With the gear wrench doo-dad it wasn't that hard at all. Much easier then what I anticipated from the way people talked about it. 10mm stubby helps on the hard to reach coils.

Must have the older waste spark engine, eh? You can covert those, I think? New coils, plugs. Not sure if ECM needs flashing.