Need Help With Spark Plug Indexing

I am indexing my spark plugs and need some advice. As far as I can tell, there are two conditions to strive for when it comes to indexing. I understand the first, which is to point the exposed flame kernel of the spark plug to the center of the combustion chamber. My plugs screw into the cylinder head at an angle, so this makes sense..All sources I have found on the internet that talk about indexing say this is the first consideration to make when indexing. I understand this, but I am unclear on the second piece of advice when it comes to indexing.

The second consideration to make with indexing is either to 1.) have exposed flame kernel slightly face exhaust valve OR 2.) have exposed flame kernel slightly face intake valve. So, which is it and WHY? I have researched this on the web with good explanations for having the flame kernel face exhaust valve and other equally good explanations for having flame kernel face intake valve.

It seems to me you'd want to have the exposed spark facing the center of the combustion chamber while SLIGHTLY facing the oncoming fuel/air charge of the intake valve. Any suggestions on this? My analysis of this is only theoretical. Has anyone had any real-world experience with this or any dyno tests to prove a slight performance increase?

*Also, does anyone have a picture of the inside of a cylinder head off a '79 KZ1000ST, so that I can see where the intake and exhaust valves are located in the tops of the combustion chambers?

I index my spark plugs by screwing them in until the plug reads the correct torque then I ride it.

If you were in a room full of gasoline vapor and struck a match, do you really think it would matter which way you were facing?

If I were riding/racing a H2 I would index. Other wise, put the plug in and ride.

XENU

i agree. the difference it makes would be the same as the weight difference on how much change you have in your pockets when you ride. my 2 cents

Same here, I don't believe anything I read that doesn't make logical sense to my brain and have pretty much been correct every time. Read STP oil treatment will ruin a wet clutch and thought BS, so tried it. Didn't faze the clutch, but didn't aid anything either. Read putting diesel fuel in gas cans will eat the galvanized metal out of the can and thought BS, so been storing diesel in metal gas cans for 20 plus years now and surprise, they still are metal. This meets my brain as another BS.

Indexing the plugs started with the Top Fuel motors. The whole entire point of indexing plugs is to ensure the electrode is in the one single place where neither the piston nor the valves will hit it.

Show me a dyno chart that shows it has any measurable effect on performance and I'll listen.

helped my dad do it once around 30 years ago on his truck,must of been one of those 60s racer things!:laugh: i want to say he pointed them more towards exhuast valve but i cant remember for sure!

RonKZ650 wrote:

Read STP oil treatment will ruin a wet clutch and thought BS, so tried it. Didn't faze the clutch, but didn't aid anything either.

Yeah, I used to run the stuff called Tufoil which is a super slick teflon based oil additive that actually had some data showing it reduced long term engine wear. Of course, as we all know, those friction reducing additives ruin wet clutches... or, at least, that's the urban myth. I ran it for about 20 years and the only effect is that I have 80k on the engine and the bottom end is still solid. The clutch actually felt smoother using it.

I guess there are some wet clutches that freak out with that kind of slicking additives, not mine. I always suspected the clutches that did needed work like new springs.

If you really want to learn about it,, HERE are search results about it.
I can't see where it would help much either.

This from NGK,

4. Indexing

This is for racers only !!
Indexing refers to a process whereby auxiliary washers of varying thickness are placed under the spark plug's shoulder so that when the spark plug is tightened, the gap will point in the desired direction.

However, without running an engine on a dyno, it is impossible to gauge which type of indexing works best in your engine. While most engines like the spark plug's gap open to the intake valve, there are still other combinations that make more power with the gap pointed toward the exhaust valve.

In any case, engines with indexed spark plugs will typically make only a few more horsepower, typically less than 1% of total engine output. For a 500hp engine, you'd be lucky to get 5hp. While there are exceptions, the bottom line is that without a dyno, gauging success will be difficult.

I won't bother,mine does 52 hp.Even 1%[0.52hp][373W]won't get that bug off the visor.

Just buy some of those spark plugs with 4 of whateverthosethingsarecalled that gap with the electrode.

I run Dynalube in my bikes. Makes shifting smoother. No effect on the clutch.....chris3

coppertales wrote:

Just buy some of those spark plugs with 4 of whateverthosethingsarecalled that gap with the electrode.

:laugh:

I love that scam..... the spark jumps across whatever point has the lowest breakdown path and all the rest is just for looks.