SuzukiSavage.com - Spark plug

Sgt_Mike

Ex Member

Re: Spark plug
Reply #15 - 11/04/04 at 16:59:28

Therefore a multi-ground plug will not perform any better and may actually perform worse than a traditional plug, unless the engine is designed for a multiple ground plug.

The above statement is from the NGK website

I dont believe that engineers design an engine around a spark plug. I do believe that spark plugs are designed to fit the application based on the technical data of the engine.

I base my statement on the fact that we at Mack Trucks Power Train Plant ask vendors to design fuel injectors, turbos and sensors to fit our application and not the other way around.

So, if the spark plug is designed to fit the application, a 4 ground electrode plug will out perform and out last a single ground plug designed to fit the same application.

I've had a set of 4 ground electrode plugs in my car for over a year and approx 17,000 miles now and they perform great. But then again, they were designed for the application.

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Savage_Rob

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Re: Spark plug
Reply #16 - 11/04/04 at 20:03:06

Yup, that's part of what I read there. I don't know. I don't design engines and multi-ground plugs were news to me just today. I am just reading and passing it along; that's why I included links in the previous posts. My take from the NGK site was that some combustion chambers (they specifically mentioned rotary engines) were designed in such a way as to require the ground electrode to be to the side of the center electrode instead of below/above it like traditional plugs. They said that this tends to hasten erosion and lengthen gaps, causing misfires (if built with a single ground). The idea behind having multiple grounds is to prolong the plug life by by spreading that erosion around between them. At least that's how I understand their description of the purpose in the design.

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Savage_Rob

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Re: Spark plug
Reply #17 - 11/04/04 at 20:24:01

Savage_Greg wrote on 12/31/69 at 16:00:11:

Could I see a picture of Iridium, please?

They have "illustrations" of the various plug features on their site but when mine arrive on Monday or Tuesday, I'll post a photo. I gather the main thing is that a standard plug has a 2.5mm center electrode, the platinum is 1.1mm, and the iridium is 0.7mm. Thaey say this reduces the voltage necessary to jump the gap and also reduces what they called "quenching". While you may already know the term, I did not. For anyone else to whom it's new, it is explained on their site at the above link better than if I tried to repeat what I read.

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PRH111

Ex Member

Re: Spark plug
Reply #18 - 11/04/04 at 22:13:59

All of the +4 and +2 plugs are designed the same with just a gap that matches the application. They do not specifically design each plug for every possible head/engine combination on the market.

Benefits: if one path has more resistance there are still other paths for a spark to fire. You don't have to worry about "indexing" the plug to face the opening towards the inlet for best combustion.

Disadvantages: multiple electrodes will increase resistance to the spreading flame front (more than the singular electrode does). You CAN'T index the plug for planning the best ignition point in reference to the inlet.

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Sgt_Mike

Ex Member

Re: Spark plug
Reply #19 - 11/05/04 at 05:39:01

PRH, your statement is correct because many engines from different manufacturers have the same characteristics therefore the spark plug requirements are the same. You can't index the plug for the best spark, you don't need to, electricity always seeks the path of least resistance to ground, the plug will index by itself. Rob, you also are right, the rotary engine is a totally different animal, it required a 2 electrode plug because the combustion chambers were/are lubricated by a engine oil mister which tends to foul a plug. I guess this topic can be controversial, like engine oil or tires, or wax, etc, etc. Have a great day .

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klx650sm2002 Serious Thumper Offline The more I learn the less I know. Posts: 2041 Cumbria,England Gender:	Re: Spark plug Reply #20 - 12/09/04 at 04:21:18 Hope this helped. Clive W
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klx650sm2002 Serious Thumper Offline The more I learn the less I know. Posts: 2041 Cumbria,England Gender:	Re: Spark plug Reply #21 - 12/09/04 at 05:29:47 What I am sugesting with the DPR8EIX-9 is to turn it into a DPR8EIX-10, ie go from 9/10ths of a mm plug gap to 10/10ths of a mm gap, or 36 to 40 thou. Clive W
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