Bosch Spark Plugs - Copper vs. Platinum - 986 Forum - The Community for Porsche Boxster & Cayman Owners

dja1980 · 06-01-2008, 02:48 PM

I'm due for my first spark plug change, and I'm having a difficult time finding the recommended plugs locally. After doing some research, I found that the OEM plugs for my 2002 3.2L Boxster S are Bosch FGR 6 KQC. The problem I'm having is that even online, these plugs are somewhat difficult to find. However, I'm am finding a lot of the FGR 6 KQE, which I believe are the same plugs, but in Platinum as opposed to Copper. Are the Copper plugs superior to the Platinum ones in any way? If so, I've got a local import parts store that can special order them for me for around $10/ea. Otherwise, I will just go with the Platinum ones, which seem to be much more readily available. I'm sure Porsche must have a good reason for using the Copper ones as OEM instead of the Platinum ones. I also called the dealership to see if they stocked the Bosch plugs, but they told me they only carry Beru. I forgot to ask whether these were Copper or Platinum though. Thanks in advance for you help... dave

06-01-2008, 02:51 PM

Buy OEM plugs. Easy to buy on the internet:

http://e-partssales.com/Merchant2/merchant.mvc?Screen=PROD&Store_Code=P&Product_Code=986plu&Category_Code=986engele

Lil bastard · 06-01-2008, 09:09 PM

Beru is also an OEM Plug.

There have been issues reported using Platinum plugs, the tips have broken off and bouced around inside the cylinders - not a desireable thing.

dja1980 · 06-02-2008, 06:59 AM

Thanks guys! So if both the Bosch and the Beru plugs are OEM is one superior to another? I know my dealership is selling the Beru ones for $14 and some change/ea. Thanks to the link bmusatti provided, it looks like I can get the Beru plugs for around $63/set shipped. I can also get the Bosch plugs from the import parts store I previously mentioned for around $63/set including tax. My point is, if both the Bosch and Beru plugs are OEM, and I can get them for the same price, should I choose one brand over the other? Thanks again. Your information has been very helpful.

Jaxonalden · 06-02-2008, 09:49 AM

My experience, I went with the Beru because I couldn’t find a set of Bosch (platinum) with dual grounding electrodes like the OEM recommends. If I could have my way I would install a four grounded electrode Iridium plug, but they don’t make those for our needs yet.

In case you ask why dual over single electrode? Exposed spark kernel.

Iridium over platinum? Iridium is harder that platinum and will not corrode or wear and you can make the plug tip the size of pin head. This coupled with four grounding electrodes means a spark that will never degrade, no matter what. And requiring less energy to operate. My Lexus came with a set installed and you don’t change them for 100,000 miles.

dja1980 · 06-02-2008, 10:48 AM

Jaxonalden - Aren't the Bosch FGR 6 KQE and FGR 6 KQC plugs four electrode? Since dual is better than single, is it safe to assume that four is better than dual? It's starting to seem like the Bosch Copper plug is the way to go?

Does anyone know if the OEM Beru plugs are Copper or Platinum?

So, from what I've learned so far...

Copper is better than Platinum because the Platinum tips can break off into the cylinders. And, Iridium is better than Platinum because it is harder and will last longer. So, is Iridium also better than Copper, or does Copper have its advantages too?

Lil bastard · 06-02-2008, 02:30 PM

Longer lasting plugs is not a great advantage for a Sports Car.

They may last longer, but so what...??? Do they stay at optimum for their entire service life??

If you're a Fleet Operator, longer life plugs can make sense.

But, Plugs give you a look-see inside the engine and can tell-tale many issues. You should remove the plugs occaisionally and see what they're telling you, plus you'll spot any issues with plug tube 'O' rings.

With access underneath, as long as you're pulling them to inspect them anyway, might as well replace them at the same time.

Jaxonalden · 06-02-2008, 07:29 PM

dja1980,

Yes those plugs have four ground electrodes but the tip is not platinum or iridium. The big difference is wear! The copper will wear quicker and you will need to change them more often. The wear comes from the tip deteriorating and expanding the gap. A platinum plug will not wear as fast (50,000 miles) and will keep it's gap giving you a properly tuned motor longer. Yea you can say I want to pull the plugs to see how things are going but why replace plugs if you don't have to. Also, these engines are run by a sophificated computer, it will properly meter itself. There's nothing you could do anyway even if you did find something. It's not like you can mess with the timing or change the jetting like on an older car.

Hope this helps because you are obviously getting allot of information, now you just have to sift through it all.

dja1980 · 06-03-2008, 06:02 AM

Quote:

Originally Posted by Jaxonalden

dja1980,

Yes those plugs have four ground electrodes but the tip is not platinum or iridium.

So, when they say that the FGR 6 KQE is the Platinum version of the FGR 6 KQC 4 electrode plug, does this not include the tip? I thought that was the point Lil bastard was making... that with Platinum plugs, it has been reported that the tips can break off. This is why I assumed that the tip is Platinum.

Yes, lots of good information, but a lot of it is conflicting in my head.