indexing spark plugs

fulltiltboogie · Post by **fulltiltboogie** » 01:20 pm Oct 29 2005

Has anyone tried "indexing" there sparkplugs on a KDX? If so...did you see in gains?

Post by **Indawoods** » 01:21 pm Oct 30 2005

I think CC did... not meaning too.

Colorado Mike · Post by **Colorado Mike** » 01:56 pm Oct 30 2005

I dunno what that is. Edumacate me.

fulltiltboogie · Post by **fulltiltboogie** » 08:14 pm Oct 30 2005

Indexing is the process of aligning the open end of electrode of your spark plug towrds the exhaust port for more efficient combustion and supposedly higher peak rpms. You would use washer(s) of various thicknesses to achieve this when you tighten your plug down.

Post by **Indawoods** » 08:18 pm Oct 30 2005

Heck... I just always used loc-tite!

(JK)

fulltiltboogie · Post by **fulltiltboogie** » 08:26 pm Oct 30 2005

Indawoods wrote:Heck... I just always used loc-tite! (JK)

Red 271 I hope.

Colorado Mike · Post by **Colorado Mike** » 08:45 pm Oct 30 2005

nice avatar. What can brown do for me?

m0rie · Post by **m0rie** » 11:08 pm Oct 30 2005

Evidently deliver a package!

Door to Door Delivery!

fulltiltboogie · Post by **fulltiltboogie** » 11:22 pm Oct 30 2005

If only they didn't handle things sooo roughly.

KDXSean · Post by **KDXSean** » 07:55 am Oct 31 2005

Rough doesn't always have to be a bad thing

Is this thread off track?????????????????

IdahoCharley · Post by **IdahoCharley** » 11:08 am Oct 31 2005

Actually indexing a plug is - alignment of the plug's open end - the plug portion open where you measure the gap - to the INTAKE CHARGE side.

Idea is full exposure of the spark to the incoming fuel mixture. i.e. not shielding the ignition spart behind the grounding electrode.

IMO - alot more important when talking about 4 cycle engines.

KDXer · Post by **KDXer** » 11:16 am Oct 31 2005

I'm guessing this would need be done with the head off ??Then again you could probably mark where the electrode is on the insulator.

canyncarvr · Post by **canyncarvr** » 04:12 pm Oct 31 2005

1. Brown delivery?

Uh...which door? Being brown and all................

OK then....

2. Yeah. What IC said. Not the exhaust port.

(NNnnnnooooo....that's not another door, delivery OR brown statement! Sheesh...get your minds out of the gutter.

...and neither is THAT! ;) )

No, I haven't ever messed with it. Besides, it's more like 'intake' than 'port'. A 2-stroke has fuel incoming from several different spots anyway. There is not just one transfer port.

Besides that...it makes a lot less difference in a hemispherical head (Yeah. My KDX's got a hemi!).

The simple answer to your question (from me..being simple and all) is:

cc wrote:No.

fulltiltboogie · Post by **fulltiltboogie** » 06:26 pm Oct 31 2005

Some say intake some say exhaust. Like you say there is not a specific path for 2 strokes but many paths form transfer ports. I think intake relates more to 4 strokes. Wouldn't you want this compressed mixture to fire at its optimum which would be facing exhaust port? Plug gap and its firing would not be exposed to incoming intake but the compressed mix at TDC. I used to always do this with jetskis and actually could get another 50-70 rpms but have never tried it on my KDX.

Post by **Indawoods** » 06:30 pm Oct 31 2005

FTB... I am so distracted everytime you post... let's see the full size version of that pic... what do ya say?

fulltiltboogie · Post by **fulltiltboogie** » 07:21 pm Oct 31 2005

OK look in the gallery. I can't figure out how to post the image here as a reply.

Colorado Mike · Post by **Colorado Mike** » 07:40 pm Oct 31 2005

I owe you FTB, <sniff> bless you man.

Post by **Indawoods** » 08:30 pm Oct 31 2005

"dunt du du dunt du du dunt delivering the GOODS!" (Judas Preist)

kdxquebec · Post by **kdxquebec** » 08:36 am Nov 01 2005

let the good times roll.

(constructive reply)

canyncarvr · Post by **canyncarvr** » 02:26 pm Nov 01 2005

Actually..I understand the process to have not anything to do with intake OR exhaust come to think of it...but to orient the plug such that the 'open' gap is facing the combustion chamber..or larger part of it anyway.

That NOT being the closed, quenched or 'flat' of an oddly configured head.

In a hemi-head motor, my guess would be that while there may well be a better direction to point the gap other than wherever it comes out to on its own accord, it would be trial and error to find that place.

So....when you find it...let us know!

**edit**
From:http://www.advanceautoparts.com/english ... 20Indexing?

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.

Note this whole indexing 'scheme' is related to 4-strokes in the first place. In a two-stroke..again...with a true hemi head...where is the most concentrated a/f section? That is likely something that changes with RPM, temperature and who knows what else.

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indexing spark plugs

indexing spark plugs