" spark plug indexing tool "
Thread Starter
Racer
Joined: Aug 2005
Posts: 469
Likes: 1
" spark plug indexing tool "
hi guys,
how are ya!
now that i brought the spak plug indexing washers kit, i saw alot of places sell the " spark plug indexing tool"!
what is the benefit of this tool?
does it help install the spark plug indexing washers easier?
from what im thinking is that you can pre install a spark plug in to this tool rather than the cylinder head and you can see which way the electrode is facing and then adjust with index washers as required.
is this about rite please?
thanks again guys!
cheers
glen
Australia
how are ya!
now that i brought the spak plug indexing washers kit, i saw alot of places sell the " spark plug indexing tool"!
what is the benefit of this tool?
does it help install the spark plug indexing washers easier?
from what im thinking is that you can pre install a spark plug in to this tool rather than the cylinder head and you can see which way the electrode is facing and then adjust with index washers as required.
is this about rite please?
thanks again guys!
cheers
glen
Australia
Instructor
Joined: Jul 2006
Posts: 249
Likes: 0
You are correct. These come in handy if it's difficult to see the plugs once they are in the heads (headers, etc.). I always just make a black stripe all of the way up the side of the plug and the socket with a Sharpie to help me see where the ground strap points. I've never owned an indexing tool.
Last edited by 106mm; Feb 25, 2007 at 09:19 PM. Reason: mistake in text
Race Director
Joined: Dec 2002
Posts: 13,348
Likes: 233
From: SCMR Rat Pack'r Charter Member..Great Bend KS
I have to ask the same question.
I've looked at all the tools...they seem to be nothing more than a nice piece of aluminum with a threaded hole.
What, exactly, is it supposed to do???? Not even the websites selling the tools explain how they work.....
I'm baffled.
Larry
code5coupe
I've looked at all the tools...they seem to be nothing more than a nice piece of aluminum with a threaded hole.
What, exactly, is it supposed to do???? Not even the websites selling the tools explain how they work.....
I'm baffled.
Larry
code5coupe
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Team Owner
Joined: May 2002
Posts: 24,337
Likes: 25
From: San Diego , CA Double Yellow DirtBags 1985..Z51..6-speed
The gap points up, or more correctly, towards the intake valve. That's what I've heard anyways.
It almost makes sense to put the ground strap in front of the exhaust valve, maybe shield the electrode better from heat fouling from the exhaust valve?
It almost makes sense to put the ground strap in front of the exhaust valve, maybe shield the electrode better from heat fouling from the exhaust valve?
Race Director
Joined: Dec 2002
Posts: 13,348
Likes: 233
From: SCMR Rat Pack'r Charter Member..Great Bend KS
Nothing. Don't worry about it.
The factories don't index plugs, and 99.99999999999999% of cars on the road don't have indexed plugs.
As some who have done back-to-back testing have said, "It won't make any noticeable difference....maybe not even any measureable difference."
Larry
code5coupe
The factories don't index plugs, and 99.99999999999999% of cars on the road don't have indexed plugs.
As some who have done back-to-back testing have said, "It won't make any noticeable difference....maybe not even any measureable difference."
Larry
code5coupe
Le Mans Master
Joined: May 2006
Posts: 9,226
Likes: 9
From: Irvine Ca
NEVER heard this one before..........Never. 
There is no Flow issue.
Compressed Fuel source is going to have the same molecular excitement no matter where it is located in the compression chamber. Hence no matter where it is ignited.....it is just ignited. Understand the Gas and Oxygen are supposed to be mixed and almost to the point where it ignites itself. Think about a Diesel, it just compresses the mixture until it explodes under the massive compression THAT has the molecules so excited/heated they just ignite and who knows where the exact point of ignition takes place.
I'm not worried if I am completely ignorant on this subject. My interest is more piqued than anything. I'd like to hear the theory, I may learn something........which would make this a great Monday.
There is no Flow issue.
Compressed Fuel source is going to have the same molecular excitement no matter where it is located in the compression chamber. Hence no matter where it is ignited.....it is just ignited. Understand the Gas and Oxygen are supposed to be mixed and almost to the point where it ignites itself. Think about a Diesel, it just compresses the mixture until it explodes under the massive compression THAT has the molecules so excited/heated they just ignite and who knows where the exact point of ignition takes place.
I'm not worried if I am completely ignorant on this subject. My interest is more piqued than anything. I'd like to hear the theory, I may learn something........which would make this a great Monday.
Team Owner
Joined: May 2002
Posts: 24,337
Likes: 25
From: San Diego , CA Double Yellow DirtBags 1985..Z51..6-speed
Team Owner
Joined: May 2002
Posts: 24,337
Likes: 25
From: San Diego , CA Double Yellow DirtBags 1985..Z51..6-speed
Actually that sort of stuff is very critical in IC design. Many cars now have 2 spark plugs in each cylinder, some with different advance to optimize the flame propogation to make best use of the combustion chamber.
Race Director
Joined: Jun 2004
Posts: 13,953
Likes: 706
From: WI
I remember reading the ground strap should be up, or toward the ex. valve like you mention. The ground strap can make a slight flame shadow.
Le Mans Master
Joined: May 2006
Posts: 9,226
Likes: 9
From: Irvine Ca
Not arguing, just probing. I'd like to learn more.
Team Owner
Joined: May 2002
Posts: 24,337
Likes: 25
From: San Diego , CA Double Yellow DirtBags 1985..Z51..6-speed
Google "spark shrouding"
I'm sure there's some relevance to it, but indexing plugs on our cars is overkill. There isn't even a consensus on which way to point them.
Racer
Joined: Nov 2006
Posts: 251
Likes: 0
From: SAN JOSE CALIFORNIA
From NGK website....
http://www.ngksparkplugs.com/techinf...300&country=US
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.
http://www.ngksparkplugs.com/techinf...300&country=US
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.
