spark plug evaluation - help - timing? running temp?

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Bextreme04

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:)

Spark plug "heat range" for the sake of this discussion, is more appropiately a measurement of time or it's actually camshaft duration - rather than temperature.

Those numbers represent - how long the spark plug actually fires. Hotter plugs fire longer than colder plugs.. the letters represent a measurement of reach into the combustion chamber.?

Aluminum wants different than iron, CC, quench, head design , operating temps, all that comes into play and sometines when people try new tech into old tech the results are often undesireable, and we have all seen that here and other threads in this msb.

Not to fault the OP but I dont know him - I believe he got sold is all. Same kind of schtick mechanics pull on unknowing women, thats the ploy for men at double the price kind of deal - if you get what im sayin. Surely the fancy new plugs will be worth the cost, right?
Know your enemy. Maybe a different source for parts would be better.

I have said this before and stand on it, often fancy platinum type plugs cannot reach their self-cleaning temperature before they foul - especially in older or higher mileage engines with looser internal tolerances and richer fuel mixtures. Especially in a wet manifold!

The darkside represents an incomplete burn. You can see the ash on the plugs!


Commence the bashfest . Look im not a pro but I used to know a little bit about it and this is common.

This is not really true....

Heat range is a measurement of the thermal conductivity of the plug, which is basically how quickly it will dissipate heat from the plug. A "colder" plug will dissipate heat faster and therefore might never get up to the correct temperature if its the wrong application. A "hotter" plug dissipates heat slower and therefore will warm up to correct operating temperature faster, but can potentially get too hot and cause pre-ignition if its in the wrong application. The plugs will fire for the same amount of time since the distributor is the determining factor on that.

The older method of AC Delco part numbering for spark plugs allowed you to determine heat range and type right from the part number. R= resistive type, 4= 14mm thread, 5= heat range(between 1-5), T= Tapered seat, S= extended tip.

The new AC Delco part numbering system does not allow for this. 41= Spark Plug, 1XX-series= Iridium, 8XX-series= Double Platinum, 9XX-series= Double Platinum Fine wire. The last two numbers of the plug are the specific application and don't denote any specific features by themselves.
 

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I plugged in your truck info to Advance Auto Website, and this is what it spit out. I filtered out the non-ACDELCO, and the fancy iridium and copper plugs.

These are the plugs for your engine. Stick with ACDELCO, your engine knows when an imposter is threaded in the heads.

CR43TS - ACDELCO Conventional

1 - ACDELCO Rapid Fire

Shouldn't your gap be 0.045? 0.035 is for a points distributor system. You should have high energy ignition in an '87 rig.
 

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Bextreme04

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I plugged in your truck info to Advance Auto Website, and this is what it spit out. I filtered out the non-ACDELCO, and the fancy iridium and copper plugs.

These are the plugs for your engine. Stick with ACDELCO, your engine knows when an imposter is threaded in the heads.

CR43TS - ACDELCO Conventional

1 - ACDELCO Rapid Fire

Shouldn't your gap be 0.045? 0.035 is for a points distributor system. You should have high energy ignition in an '87 rig.

I agree it should be .045"... it should also be noted that Iridium AC Delco plugs are often actually NGK Iridium plugs and will still have the NGK part number stamped into the plug, even though they are labeled AC Delco. I'm sure a lot of the other "AC Delco" plugs are actually just rebranded plugs of some other manufacturer as well. Not saying he shouldn't use AC Delco though. I guess my point here is that while another brand plug wont necessarily be the wrong plug for your truck(and might actually be identical to the AC Delco plug), the AC Delco plugs will definitely be the right ones.. The AC Delco's are often actually cheaper than the same part number of another brand
 

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I agree it should be .045"... it should also be noted that Iridium AC Delco plugs are often actually NGK Iridium plugs and will still have the NGK part number stamped into the plug, even though they are labeled AC Delco. I'm sure a lot of the other "AC Delco" plugs are actually just rebranded plugs of some other manufacturer as well. Not saying he shouldn't use AC Delco though. I guess my point here is that while another brand plug wont necessarily be the wrong plug for your truck(and might actually be identical to the AC Delco plug), the AC Delco plugs will definitely be the right ones.. The AC Delco's are often actually cheaper than the same part number of another brand
I have a perfect example of this in the plug I posted earlier
itr4a15 Ngk
41-101 ac delco plug number
12568387 gm SPO/CCA
You must be registered for see images attach
 

82sbshortbed

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Copper plugs can eat a fat dick!
 

82sbshortbed

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Sounds like someone is a bit jealous

No, copper plugs are trash imo. They're put in at the factory and I've never had good luck with them.
 

Bextreme04

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No, copper plugs are trash imo. They're put in at the factory and I've never had good luck with them.

To be fair, GM hasn't put a copper plug in an engine, from the factory, for at least 30 years.

The cheapo copper plugs make a lot of sense in our motors because they are usually leaking enough oil into the combustion chambers from bad valve seals and leaky intake manifold gaskets and are usually tuned poorly enough that they end up fouled with carbon long before a platinum or iridium plug would be end of life.
 

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My 77 chevy hei loves old fashioned plugs.I've tried platinum before.They just dont last as long in it because they start underperforming after several thousand miles.Those coppers just run smoother in it,even after quite a few miles.
 

82sbshortbed

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To be fair, GM hasn't put a copper plug in an engine, from the factory, for at least 30 years.

The cheapo copper plugs make a lot of sense in our motors because they are usually leaking enough oil into the combustion chambers from bad valve seals and leaky intake manifold gaskets and are usually tuned poorly enough that they end up fouled with carbon long before a platinum or iridium plug would be end of life.


The last vehicle I had them in was my 05 dodge Dakota. They went bad with no warning and was almost stuck in Houston on the way home from work. Luckily I was able to limp it home. I just filled up and thought I had water in the gas with how it was running. Come to find out it was the plugs. Lol
 

AuroraGirl

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No, copper plugs are trash imo. They're put in at the factory and I've never had good luck with them.
I was making a joke. But I use copper on my old Saturn because ignition components just die without that, my old stuff like square atm because I’m definitely using severe maintenance criteria and cheap vs expensive would be getting replaced equally often, and if an engine is easy to access plugs, it’s not hard or inc9nvenient for some to replace often
 

Octane

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The last vehicle I had them in was my 05 dodge Dakota. They went bad with no warning and was almost stuck in Houston on the way home from work. Luckily I was able to limp it home. I just filled up and thought I had water in the gas with how it was running. Come to find out it was the plugs. Lol
Gosh,even my 97 and my 01 mazda trucks used platinum plugs.
 

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