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TRAV05
07-11-2006, 07:16 AM
Has anyone ever tried indexing the spark plugs for more power... I started to look into it after some one told me its an easy way to gain some power.

Thanks

ohsobad_chevy
07-11-2006, 08:08 AM
d-e-t-o-n-a-t-i-o-n :devil:

400exstud
07-11-2006, 09:21 AM
I've done it to my snowmobile but it didn't do anything.


How would it create detonation?

rooster300ex
07-11-2006, 09:33 AM
What is indexing a spark plug.

TRAV05
07-11-2006, 10:10 AM
What Is Indexing?
Generally speaking, the idea of indexing is to position the spark plug so that its gap is facing the center of the cylinder, angled slightly toward the exhaust valve—the most common arrangement. (Some engines work better with other gap locations.) This is important because, as the piston approaches TDC, the air/fuel charge is being compressed. The charge or "mixture" is being forced toward the area of the spark plug—and normally, the exhaust valve. The true speed of this force inside the combustion chamber is extremely fast. Some experts speculate that it surpasses supersonic speeds.

Because of this, the spark generated from the plug should be in a "position" to create the best possible flame front. Looking at a typical side-gap spark plug, you'll note that the electrode can actually block the flame process. On the other hand, if the electrode gap faces the on-rushing air/fuel charge, it stands a much better chance of igniting a flame front.

How To Index
How is a spark plug indexed? Simple: Mark the spark plug insulator body with a felt marker (never use a pencil, which acts the same as a carbon track inside your distributor cap) on the side where the ground electrode attaches to the spark plug body. Instead of rummaging through boxes of spark plugs to find the elusive combination of perfect plug threads that match the cylinder head threads, use indexing washers. These soft copper washers are available from the aftermarket and will fit both flat- and tapered- seat spark plugs. They're available in three thicknesses: 0.060-inch, 0.080-inch and 0.100-inch.

Copper's inherent softness along with the various washer thicknesses make it simple to thread the spark plug into the cylinder head and tighten it to the point that the index mark is situated in the correct position relative to the combustion chamber. (Never double up washers; they aren't intended to be used in tandem.)

ohsobad_chevy
07-11-2006, 12:21 PM
Originally posted by 400exstud
I've done it to my snowmobile but it didn't do anything.


How would it create detonation?

I thought he was talking about something else, my bad.
Learn something new everyday... Does indexing really work?

bwamos
07-12-2006, 07:58 AM
Sounds logical to me.

red2004 TRX450R
07-12-2006, 09:04 AM
we done it on V-8 car motors, they have a wedged shaped head/combuston chamber, and the plug is set off to the side. most quad had the plug in the middle, so on a quad it may not help as much as a car.

we allso cut the ground electrode back some.