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spark plug evaluation - help - timing? running temp?

Discussion in 'Engine & Performance' started by Jwernatl, Apr 8, 2021.

  1. Bextreme04

    Bextreme04 Full Access Member

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    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.
     
  2. DoubleDingo

    DoubleDingo When In Doubt, Throttle Out

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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.
     
  3. Rusty Nail

    Rusty Nail Victim of Culture

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    A little , but not likely for the same reasons you may suspect.


    True enough for the sake of this discussion. ;) thanks for the help.
     
  4. Bextreme04

    Bextreme04 Full Access Member

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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
     
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  5. AuroraGirl

    AuroraGirl Full Access Member

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    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
    456FAD3D-0157-4929-9E1A-42FC4C7E9056.jpeg
     
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  6. Rusty Nail

    Rusty Nail Victim of Culture

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    omg that fucking sucks!
     
  7. 82sbshortbed

    82sbshortbed Fuckemall!!

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    Copper plugs can eat a fat dick!
     
  8. AuroraGirl

    AuroraGirl Full Access Member

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    Sounds like someone is a bit jealous
     
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  9. 82sbshortbed

    82sbshortbed Fuckemall!!

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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.
     
  10. Bextreme04

    Bextreme04 Full Access Member

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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.
     
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  11. Octane

    Octane Full Access Member

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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.
     
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  12. 82sbshortbed

    82sbshortbed Fuckemall!!

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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
     
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  13. idahovette

    idahovette Full Access Member

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    @82sbshortbed Yeah Doug, but in all fairness it was a doddgge!!!!....lol
     
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  14. AuroraGirl

    AuroraGirl Full Access Member

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    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
     
  15. Octane

    Octane Full Access Member

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    Gosh,even my 97 and my 01 mazda trucks used platinum plugs.
     

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