indexing spark plugs

[Cheepjeep85]

has anyone took the time to index their spark plugs? what where your results? was it worth doing? i want to do it i just figured i would ask before i went up to the speedshop to get the copper washers for it, never tried it before

 

[Old Dog]

I never tryed it, always thought it was just a race car thing. If you do it let us know if it helped any.

 

[BajaEdition]

I think I would try one of those multi plugs before indexing, just an opinion, I think the length the spark plugs go in is more important than the direction of the spark.
Now, when indexing do you face the spark for the direction that engine causes the fuel to swirl? and what direction is that in your engine? Or is it something else we are trying to match?

 

[TDHofstetter]

Given that the arc won't jump in any particular direction, there won't be any more than a teeny tiny miniscule difference... and that difference will only appear at ALL when the spark is "shadowed" from the intake stream by the top strap. If the top strap isn't shadowing the center electrode, there won't be any difference at all.

Remember, the arc will jump all around the rim of the spark plug just like in one of those Tesla coil ball things.

 

[BajaEdition]

ThAt is what I thought

 

[mhubacek]

Indexing? First I've ever heard of that. Is there some sort of spacer that is used to change the direction and depth of the spark plug electrode? I think that is what I'm gathering.

 

[Cheepjeep85]

well your supposed to index the open side of the plug towards the exhaust valve, mhubacek you use copper indexing rings they look just like a copper washer but they have a measured thicknes. my neighber who used build alot of VWs said it done wonders for them thats why i figured i would try it on the jeep. but baja i believe you are right it would probably be whole lot better to use a different plug, i plan on going with the e3's i just figured i would try this, first

 

[mhubacek]

Interesting, thanks for the info.

 

[Old Dog]

here's something else you can try, I have never done it but plan on trying it sometime.Performance Unlimited 4-Wheel & Off Road Center - Hartford, Wisconsin - USA Technical Documents

 

[Cheepjeep85]

thats pretty good, i may try that with these plugs. i'll still eventually buy the e3s but i figure i would see what i could get out of these before i do

 

[TDHofstetter]

here's something else you can try, I have never done it but plan on trying it sometime.Performance Unlimited 4-Wheel & Off Road Center - Hartford, Wisconsin - USA Technical Documents

That's an interesting article - side-gapped plugs seem more more promising than indexed plugs. I'd guess that you'd need to select a plug that's one or two ranges colder than normal, since a fatter spark will tend to get the tip hotter.

I may well run a trial of that one myself.

 

[CJ]

I indexed all my plugs in my 100 yard dash days. Was it worth it? Hell if I know - but it was one more thing that 'supposedly' kept me on top of my competition.

With the advent of the Bosch multi electrode plug and the E3, I just don't see the reason to do this.

 

[dslywalker]

Sparkplugs.com - Spark Plug 411 found this while checking out E3 plugs.Had some good info
Mike

 

[BajaEdition]

I guess this goes as one of those things that goes and proves worth in racing circles. What I mean is, once you have done all the big things, you have to go with the little things, and then after that, the little little things. And finally it is the guy who is the most anal who wins.
What I mean is at some point, every little item counts, but then to those not in that level of competition, does it matter?
I also know technology moves on, and more and more of the multi pronged side fired spark plugs enter the market. So now do we index old tech plugs or use new tech side fires?

 

[TDHofstetter]

I guess this goes as one of those things that goes and proves worth in racing circles. What I mean is, once you have done all the big things, you have to go with the little things, and then after that, the little little things. And finally it is the guy who is the most anal who wins.
What I mean is at some point, every little item counts, but then to those not in that level of competition, does it matter?
I also know technology moves on, and more and more of the multi pronged side fired spark plugs enter the market. So now do we index old tech plugs or use new tech side fires?

Well said.

Do the sidefires actually do anything we can see & feel if we're not fanatical brilliant race tuners?

 

[LongHorn]

IMHO you get more benefit from "Side Gapping" than indexing.

 

[BajaEdition]

Well said.

Do the sidefires actually do anything we can see & feel if we're not fanatical brilliant race tuners?

I can see the appeal of indexed plugs, it does make sense. However a sidefire style plug is doing the same thing, I.e. getting the flame possibly being behind an electrode and being in the path of the fuel swirl. I think a Hei conversion, if your Jeep is old enough not to have it, would be more effective.
IMHO:driving:

 

[LongHorn]

I can see the appeal of indexed plugs, it does make sense. However a sidefire style plug is doing the same thing, I.e. getting the flame possibly being behind an electrode and being in the path of the fuel swirl. I think a Hei conversion, if your Jeep is old enough not to have it, would be more effective.
IMHO:driving:

The beauty of sidegapping is not only do you get a bigger flame kernel its also free, Vs. the more expensive plugs or copper index washers.
I'm already running HEI.

 

[Cheepjeep85]

yep me too (hei) i'm running bosch platinum tips right now but im not very happy with em, they are just a regular plug with platinum tips, i was gonna to some testing with em before i dropped $45 on the e3s which i know are well worth the money

 

[TDHofstetter]

Hmmm... I see they (the folks selling the E3s) claim about a 7% efficiency benefit over "conventional" plugs, less over platinum plugs. Seven percent translates to... lessee. Starting with, say, a 150HP engine with stock conventional plugs, that'd bring it to nearly 160. Starting with 15mpg, it bring efficiency up to slightly better than 16.

It's an interesting design, for sure.