|06-11-2013 10:52 AM|
The reason for indexing Spk Plugs is to locate the wire of the plug so the dome on the piston would not hit it , then some one got the idea this should be done on all engines , like most things people put to much thought into turns out the only reason to index a plug is to keep it away from dome pistons
If you want to expose more of the kernal (which is the theory behind indexing) then us the Autolite AR series plugs these give you the fastest kernel growth and exposure then any other plugs
|06-11-2013 09:44 AM|
|Roadworthy||Yeah, the gains for indexing on this type of engine might be null. I bought some new stock plugs but still have my cut ones I can take pics of.|
|06-11-2013 09:41 AM|
|TboneZX3||In the stratified fuel/air charge environment of a DI cylinder, it's not likely that indexing or profiling will help at all. And, obviously, you can't face the electrode toward the piston in a DOHC engine like this, since the plug is centered vertically at the top of the cylinder. I suppose you could try to index so the electrode faces the injector, but that's not likely to be worth the effort.|
|06-11-2013 09:39 AM|
Now then a gap-less plug like BRISK LGS or BOSH +4 might do a little.
|06-11-2013 09:36 AM|
Been there done that :P
Can't really index the plugs properly without inserts and an different plug length. I did file down my original plugs to be side firing and maybe it helped, but hard to tell. Seemed to fire about the same.
|06-11-2013 08:35 AM|
indexing and filing spark plugs
Back in the day, we used to "index" the spark plugs so that the opening would face down toward the piston so that as much of the spark as possible would ignite the A/F. We would also"file" the sides of the electrode so that, assumably , some of the spark would fire around the electrode.
Do you think this would be worth the effort on our FoFo's? Below is a link to an article if you need more info.