Indexing of Spark Plugs

[powerband]

The Performance Six Engine I'm researching has Indexed spark plugs, the Electrodes are marked on the wrenchable part. How have you heard this is supposed to be important?.

Powerband

 

[Anonymous]

yes the ford six hand book mentions this however i dont think it makes that big of a difference in performance, nothing noticeable. It doesnt make a difference, how they go in, in theory by having the open end of the diod in facing the valve the fuel would drop into the spark plug not on top.


wes

 

[rbohm]

8) indexing plugs is an idea that the racers have used for years(decades actually). the gains are small, but when you are racing, it can mean the difference between winning and losing. on the street you will never see the difference.

 

[CobraSix]

8) indexing plugs is an idea that the racers have used for years(decades actually). the gains are small, but when you are racing, it can mean the difference between winning and losing. on the street you will never see the difference.

Pretty much.

By indexing, you put the open part of the plug towards the intake valve. This allows the spark to see a better start for the fuel mixture for ignition.

Again, small beans. Not worth the effort on a street engine. You'l need about 8 plugs to do this on a 6 cylinder engine. It's trial and error to fine one that lines up right with the right amount of torque applied.

Slade

 

[ludwig]

I got a blister pack of indexing washers in 3 different thicknesses from my local speed shop. Don't need no stinkin' 8 plugs for a six, dog.