Hi,

is there any final opinion on how multi-ground spark plugs behave on 996/997 cars? I ordered online set of NGK Laser platinum BKR7EQUP #4285 plugs, photo on web site had stock original image of single-ground electrode and pointed central electrode, instead of it I received set of plugs that do look like these:

http://www.amazon.com/gp/product/com...au_pf_dp_chart

So I wonder now if I should spend my time and demand replacement to get those:
http://www.ngksparkplugs.com/product...m.asp?mode=nml

Or are they all the same? I wonder still why official NGK web site does not even show those multiground ones at all.

 

From the web:

"Some combustion chamber designs (such as a rotary motor) require that the spark plugs have the ground electrode placed to the side of the center electrode rather than below as on a traditional plug (see photo). This firing tip design tends to erode the tip of the ground electrode faster than a traditional plug. Erosion at these points creates a larger gap between the center and ground electrodes, causing plug misfire. Thus, by having more ground electrodes, you extend plug life. It is important to note that multi-ground does not mean multi-spark, there will still only be one spark at a time. 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."

 

Hmm... And how does it apply to our 997?

 

I interpret it to mean avoid them since the 997 wasn't specifically designed for them.

 

So, consensus is - those multi-ground plugs are no good?

Any other opinions out there?

 

Have you ever owned and Alfa? They used to used multi-prong plugs by Lodge. They may even still do.

Point is most of us threw them out and put in "normal" plugs. Cheaper and less fouling. Never did understand the reason for them in the first place.