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Spark plugs - non O.E.?

5035 Views 13 Replies 10 Participants Last post by  srmarti
Has anyone experimented with non-OE (i.e. non-Iridium) plugs in our ICEs?

It has been a long standing argument among the VW community (cars in the 2000s and newer generations) that you get (significantly?) better fuel economy with Copper plugs over Iridium at the cost of the plugs wearing out 2-3x faster.

At present I drive a lot of ICE miles, so I'd be willing to Guinea pig myself if I can determine what plugs are "compatible"
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I'm skeptical. Once you have sufficient spark for consistent ignition what exactly is more going to do? How much better fuel economy improvement is "significant"? Are they simply comparing worn out Iridium plugs to new copper ones? Maybe the Iridium are still performing well while the copper ones are already shot and need replacement? How does that figure into the economics?
this is actually a widely debated topic in the VW community... the only plus side that can be agreed upon with Iridium plugs is the 60-100k mile service interval (vs 20k on Coppers). And when I say "significant", I'm talking 10%, so... 4-5mpg highway (observed on both the 1.8T and Vr6 2.8L engines)? May not be significant to EV mode drivers, but I drive about (at present) 75-80% ICE, that would equate to 40ish miles to a tank... or 1 gallon @ $3/gallon... the cost of two plugs. Based on my typical annual driving a savings of about $65/year, or almost $200 in gas between plug changes.

naysay or not, I plan to give this a try, just curious if anyone on here has experimented
I'd like to see test results of new iridium plugs vs. new copper plugs. Ideally it should be double blind so the driver doesn't bias the results. 20k copper plugs vs. 20K iridium plugs might be interesting too. 10% over worn out plugs, yea I guess so, maybe. 10% better than new plugs, I doubt it.

Look forward to seeing your results.
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