All around best spark plug for Inline 6?

[98XJeep]

bosch platinum plugs have a bad problem with the center electrode falling out, which will cause missfire's. you have to look very close to tell but once you've seen two side by side, one without it and one with, you'll know.

 

[KG6ZJM]

I've been running the bosch platinum +4s for some time now... Are they doing anything for performance? I have no idea. I though I felt a difference when I installed them, but that may have been in my head, or because the old plugs were dirty or gapped wrong. Who knows... Either way I cracked one, so I had to replace them, and the bosch plugs were on sale. I guess the important part is that they haven't caused me any troubles. Anyone know the life of these plugs btw? I haven't changed them in.... a long time!

Edit: Spelling and grammar... sorry I'm drugged out on cough meds

 

[Ecomike]

I've been running the bosch platinum +4s for some time now... Are they doing anything for performance? I have no idea. I though I felt a difference when I installed them, but that may have been in my head, or because the old plugs were dirty or gapped wrong. Who knows... Either way I cracked one, so I had to replace them, and the bosch plugs were on sale. I guess the important part is that they haven't caused me any troubles. Anyone know the life of these plugs btw? I haven't changed them in.... a long time!

Edit: Spelling and grammar... sorry I'm drugged out on cough meds

Yes, but what year is the Jeep ignition system??????

Please post the year of the ignition system with the plug choice and plug history as it may be critical data for us all! The computers, electronic speeds, and ignitions have changed substantiall between 87 and 00.

 

[Highlander]

I've been running Bosch single platinum AP3924 spark plugs on my 87 Renix, currently 249,000 miles, 24,000 miles on the Bosch single platinum AP3924 spark plugs so far and they still look like new, gap has not worn in 24,000 miles.

I am planning some plugs and gap experiments on mine soon to see how mileage is affected, but to my knowledge the plugs I am running work fine with the Renix engine and Renix stock set up. Most of my problems were bad wiring harness wiring, worn out sensors, and worn out parts, not the choice of spark plugs, but I have never tried the other plugs so I may not know what I am missing?

pssst.....
those are autolite single platnum numbers :mrgreen:

 

[rcmf5525]

No plug ever will make a huge difference by themselves but a quality plug with quality wires, distributor cap/rotor, and coil will make a noticeable difference. Mostly in throttle response and small difference in MPG.

Platinum and iridium are poor conductors of electricity. Why would any one make plugs using these materials? They are very dense and that equals longevity (not performance).

When I upgraded my coil, wires and distro cap/rotor, I wanted to get a plug that would compliment the other upgrades. At that time I knew of only three electrode materials used in sparkplugs: Copper, platinum, and iridium. Copper being the most conductive, I was going to go with some basic plugs until I stumbled upon Nology Silver plugs. Their electrodes are made of silver, which is a much better conductor than the other three. Only surpassed by gold, which would be quite expensive. This tune up was the first thing I upgraded on my XJ, and I noticed a difference. I’m not saying the silver plugs made the difference, but the combination of all the components did. The plugs are pricey and wont last as long as the regular old Champions, Autolite, or NGK copper plugs, and certainly not as long as any of the platinum or iridium plugs, but I am OK with that.

Science says the plugs should be more a more efficient carrier of electricity and that is enough for me.

 

[slobo]

I get more flex when I run with Champions, :dunno:

 

[rcmf5525]

lastara

 

[Ecomike]

No plug ever will make a huge difference by themselves but a quality plug with quality wires, distributor cap/rotor, and coil will make a noticeable difference. Mostly in throttle response and small difference in MPG.

Platinum and iridium are poor conductors of electricity. Why would any one make plugs using these materials? They are very dense and that equals longevity (not performance).

When I upgraded my coil, wires and distro cap/rotor, I wanted to get a plug that would compliment the other upgrades. At that time I knew of only three electrode materials used in sparkplugs: Copper, platinum, and iridium. Copper being the most conductive, I was going to go with some basic plugs until I stumbled upon Nology Silver plugs. Their electrodes are made of silver, which is a much better conductor than the other three. Only surpassed by gold, which would be quite expensive. This tune up was the first thing I upgraded on my XJ, and I noticed a difference. I’m not saying the silver plugs made the difference, but the combination of all the components did. The plugs are pricey and wont last as long as the regular old Champions, Autolite, or NGK copper plugs, and certainly not as long as any of the platinum or iridium plugs, but I am OK with that.

Science says the plugs should be more a more efficient carrier of electricity and that is enough for me.

First off, thanks for the post, nice to have a fresh perspective, different ideas and success stories, that said, I am not buying the electron conductivity story here! I am not a spark plug expert yet, but IIRC correctly there seems to be a lot of importance placed on having the correct internal resistance, i.e. resistor plugs, and not conductivity, and the correct internal resitance in the plug wires as well. I suspect it may have something to do with building up the voltage in the SP wire and plug electrode and limiting the electron leakage across the spark gap as the coil charges up the plug electrode and wire to some critical saturation point, or voltage before the gap sparks. Just an educated guess on my part based on what I have read this week, and my education in physics. Seems there should be a critical capacitance and impedence in the wire and electrode system based on some resistance (impedence) . Also, the electron path during the spark is at elevated temperatures, and pressures inside an explosive atmosphere and not between two metal to metal surfaces or through a bulk metal wire, which is the electrical conductivity your are quoting.

 

[Ecomike]

pssst.....
those are autolite single platnum numbers :mrgreen:

Thanks, one of the things I like about this place, always some one around to keep me honest!

I thought my notes seemed odd as I thought they were autolite, but I just figured I was thinking of the second set of plugs I just bought for my 4th jeep, but you are right, I think, so I corrected my old notes, thanks.

So for the record, I have been using Autolite single platinum AP3924 spark plugs, and not Bosch!

 

[KG6ZJM]

Yes, but what year is the Jeep ignition system??????

Please post the year of the ignition system with the plug choice and plug history as it may be critical data for us all! The computers, electronic speeds, and ignitions have changed substantiall between 87 and 00.

Right, sorry as I said I was all druged up on cold meds. You should have seen the post before I let google have a go at correcting it. I don't think it was even english!

That said, its a stock '89 ignition system. I've only changed the plugs and put on the "good" wires from autozone. I put the good in quotes because it's just what the sales guy there told me. I didn't really put any research into it. I did like that they had a lifetime warenty though!!! I think that sold me more than anything else. I do have what is left of an MSD custom length cable kit in the garage left over from another project, and have been meaning to make a set for the heep, but you know what? I'm a lazy bastard!!!:laugh3:

 

[rcmf5525]

First off, thanks for the post, nice to have a fresh perspective, different ideas and success stories, that said, I am not buying the electron conductivity story here! I am not a spark plug expert yet, but IIRC correctly there seems to be a lot of importance placed on having the correct internal resistance, i.e. resistor plugs, and not conductivity, and the correct internal resitance in the plug wires as well. I suspect it may have something to do with building up the voltage in the SP wire and plug electrode and limiting the electron leakage across the spark gap as the coil charges up the plug electrode and wire to some critical saturation point, or voltage before the gap sparks. Just an educated guess on my part based on what I have read this week, and my education in physics. Seems there should be a critical capacitance and impedence in the wire and electrode system based on some resistance (impedence) . Also, the electron path during the spark is at elevated temperatures, and pressures inside an explosive atmosphere and not between two metal to metal surfaces or through a bulk metal wire, which is the electrical conductivity your are quoting.

You might be correct; I will not even pretend to know that much about it. So, you are saying you want resistance? I would think that the less resistance would mean hotter spark there for more fuel being expended in the cylinder. Is that wrong? Nology also makes wires with capacitors inline. What would be the benefit of that? Hotter spark right?

 

[Ecomike]

Right, sorry as I said I was all druged up on cold meds. You should have seen the post before I let google have a go at correcting it. I don't think it was even english!

That said, its a stock '89 ignition system. I've only changed the plugs and put on the "good" wires from autozone. I put the good in quotes because it's just what the sales guy there told me. I didn't really put any research into it. I did like that they had a lifetime warenty though!!! I think that sold me more than anything else. I do have what is left of an MSD custom length cable kit in the garage left over from another project, and have been meaning to make a set for the heep, but you know what? I'm a lazy bastard!!!:laugh3:

OK, so as I understand it you are succesfully using bosch platinum +4s for some time now on an 89 Renix Jeep, right? So now all we need for you to do is post the actual part number on those plugs since they come in different heat ranges (I think?), and of course since you are lazy, and need some motivation, we will toss in 100 Brownie points if you post the part numbers today!:laugh3:

 

[Ecomike]

You might be correct; I will not even pretend to know that much about it. So, you are saying you want resistance? I would think that the less resistance would mean hotter spark there for more fuel being expended in the cylinder. Is that wrong? Nology also makes wires with capacitors inline. What would be the benefit of that? Hotter spark right?

Right, but....Well I started out yesterday reading all the old threads around here on the spark plugs topic, and there was some discussion by those with a lot more experience than me discussing that very topic, capacitive spark plugs. Someone said we need to be careful because too hot of a spark (what ever that is?) could burn up our engine internals, as I recall they were warning us to use resistor plugs and not exotic capacitive plugs or non resistor plugs on our stock engines.

I suspect there several issues, one is spark initiatation (timing effects casued by gap, and resistance....) , spark duration, and peak spark energy intensity.

The nice thing about platinum is it takes a huge hammer (figuratively speaking BFH ) to burn, oxidize or melt it compared to other metals, so they use it as a surface coating over the base metal to protect the base metal from errosion, corrosion and oxidation so that the spark gap stays the same for more miles.

The other important factor is heat range which has to do with the thermal conductivity and total heat capacity of the ceramic cone insulator around the electrode. It needs to have the right conductivity and heat capacity to get hot enough to burn off carbon deposits while not melting and not letting the electrode itself melt. If too hot parts melt, if too cold it gets carbon fauled very quickly.

I am hoping to get a lot of actual MPG and spark plug used crossed over to actual engine igniton system years data to see if there is not some significant differences out there in mileage for various spark plugs. The topic is further complicated with the fact that our OEM data was based on fuel that is no long made here in the USA. Most of it is aproaching E10 ethanol blend status which I think burns slower than our old gasoline formulas, which might mean we should start using a different spark plug? :eyes:

 

[KG6ZJM]

ok, i'll do it! it probably won'y be till a bit later though. I have a lunch thing I have to go to in the city today. I'll pull some plugs when I get back. It'll probably be good to tak a look at them anyhow.

 

[XJ98Jeep]

I heard if you use Bosch plats your jeep will fold like a taco.

 

[rcmf5525]

I heard if you use Bosch plats your jeep will fold like a taco.

That is like the third time I have see the quote 'fold like a taco' in the last month. :doh:

 

[carnuck]

I put some dual ground NGKs (BKR6EK I think) 2288 and cut the ping in mine.

 

[gorman]

I went to the dealer and asked for six new sparkplugs and they handed me a nice little Mopar box containing six smaller Moper boxes. When I took the plug out it was an NGK ZFR5N exactly as specified on the NGK website too. Funny thing was that these sparkplug in their fancy Mopar boxes at the dealer worked out cheaper than a similar NGK plug at Autozone...