I index the spark plugs on my moddified street bike to aid with spark.

What I do is buy double the plugs and simple mark the direct insert and see where the tip is pointing. If it points to the intake then its indexed. If not I try another plug.

Anybody else put forth the extra effort?

 

please explain, apparently i have ben living in a cave and dont know what this is.

 

Burns the fuel more efficently, but you won't se a bit of difference on a street car. Really for high performance race builds running high RPM.
You need to buy a pack of indexing washers to do this. You don't do it by going through 20 plugs to find the ones that screw in right.

 

There was no performance increase with mine when I indexed the plugs ( using indexing washers) It might be worth a few ponies... but I didnt think it was worth the effort on a street performance car?? yes??

Just me.............................

Thumper

 

From what I've heard, indexing plugs works well in vehicles that see a lot of boost, excessive RPM, or a lot of fuel under high load. For 98% of the street cars out there, not worth the effort.

 

• The Hybrid Honda Insight 70mpg car came factory with indexed sparkplugs. No washers needed. The factory measured out the index aligment and created I think 4 different sparkplugs (A,B,C D).
• I index plugs on my v-twin motorcycle by simple using a marker. Install and see if it lines up then try again if needed. No need for 20 plugs. It only takes 4 plugs for me to do 2 cylinders.

 

Such as overdrive pulleys... Indexed plugs help with detonation. Better flame control.


http://www.fordmuscle.com/archives/2000/07/indexplugs/

"There is a lot of debate and skepticism to whether or not spark plug indexing is worth the effort. Some studies have shown 1-2% of total engine power can be lost through poor spark direction. Perhaps that does not sound like enough power to be concerned about, but consider this: Chances are that you, like the majority of enthusiasts, have spent a fair amount of money on hotter coils, ignition boxes, better plugs, ignition wires, cap and rotor, and the list goes on. In fact many heads these days boast "revised spark plug angles" and "fast burn" chambers. Heck, you probably even made the extra effort to set all your plug gaps to the exact specification. Well if you believe all those things make a difference, and they probably do, than it is only logical to think that the spark needs to face the right direction in the combustion chamber!"



"Indexing spark plugs has been practiced by motoring enthusiasts for many years. The technique has been used by racers to obtain maximum combustion efficiency (which is why the Hybrid Honda Insight uses them - far from a sports car but is the leader in efficiency at 70-100mpg) within each cylinder, and also to maintain consistent combustion between all cylinders. The object of indexing spark plugs is to ensure that a spark plugs ground electrode is not positioned in such a way where it is shielding the spark from the fuel/air charge or impeding the flame front as it travels away from the spark plug into the chamber. The ideal position of the plug in the head is such that the gap is facing towards the valves, so that the spark is fully visible to, and aimed at, the center of the combustion chamber.

Unfortunately with today's mass produced plugs and cylinder heads, there is absolutely no assurance that when you screw in a sparkplug it ends up in the correct orientation. The majority of people take this for granted, and probably feel the minimal horsepower gains is not worth [FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-1]the added effort. But then again, the guys winning races aren't just following the majority!"
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[FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-1]The rest of the article explains the method I have talked about. Mark the spark plug and see where it lines up once installed.[/SIZE][/FONT]
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[FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-1]http://www.ehow.com/how_2001164_index-spark-plugs.html[/SIZE][/FONT]
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[FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-1][SIZE=3][FONT=Georgia]Step 1:
[/FONT][/SIZE]Open hood and remove spark plugs.
[SIZE=3][FONT=Georgia]Step 2:
[/FONT][/SIZE]Mark each spark plug where the electrode is attached to the spark plug body.
[SIZE=3][FONT=Georgia]Step 3:
[/FONT][/SIZE]Identify where the exhaust valve is located on your engine block.
[SIZE=3][FONT=Georgia]Step 4:
[/FONT][/SIZE]Screw in a spark plug and check if the mark on the spark plug is pointing away from the exhaust valve. Tip towards the intake valves. Plus or minus 20 degrees. If they do not line up, use indexing washers (they come in different thicknesses) to align the electrode away from the exhaust valve. By pointing the spark plug electrode away from the center of the chamber, it provides unobstructed spread of the spark flame. Or remove spark plugs and try another one. Indexing washers and extra sparkplugs will be about the same cost.


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Yep, they sure do. Which reminds me...I need to check ours...105k miles is coming up very soon.

 

I have a large assortment of shims and will even sand them if necessary to get things perfect.

Have always done so for street cars because, especially with 4-cylinders, it always seems to make the idle noticeably smoother. The power difference will never be noticeable as it is barely even measurable.

The theory behind it is having the electrodes pointing in some directions can delay flame propagation, and thus have the same effect as varying the effective timing advance for only those cylinders. If the head is off, it's worthwhile to go the extra step and dremel off extra threads/edges that can cause preignition too.

 

That does make more technical sense. I just thought it helped with ignition. But I see what your talking about. Would really play a role when those pistons are running high RPM.

 

We indexed the plugs in our Drag Racers back when. Now with quad tipped platinum plugs it kind of went south on street cars. Iridium plugs might use the indexing.

 

If you use the proper plug (NGK BKRxEQUP) then there is no need to index, it has 4 ground electrodes, the spark is open to the bottom, and the MINI head is hemispherical

 

not to be confrontational ; but doesn't the electrode as explained block the flame front ? don't get me wrong i thought the 4 electrode plugs were cool too . this should be a good discussion .

 

BMW chose the NGK laser platinum EQUP plug for good reason, it works better in a hemi head and because they are self-cleaning, the spark is forced to cross the tip of the ceramic cleaning it in the process (no other plug design does this) allowing the ceramic to pull heat from the combustion chamber, which is the job of the plug and reason for the specified heat range. A colder plug removes more heat, the actual spark temperature or intensity is the same. If the ceramic is allowed to get dirty, less heat is removed and negates the reason for using a colder plug in the first place.
I'm not saying that the iridiums don't work, but the original point was that if you use the EQUP plug, then indexing is not needed. In all honesty, I do not know the direction of the flame front, however I cannot see how it would be blocked with the 4 ground electrode plug.

 

Based on BMW's choice of the laser platinum plug which plug is recommended for the JCW?

 

The stock plugs would be the recommended ones. They are a step colder than stock.

 

The stock JCW plugs are a step colder than the stock MCS plugs?
Are those only available at MINI dealers or any corner auto store?

 

The JCW plug is a BKR7EQUP (stock is BKR6EQUP)
They are not available at any corner store, MINI dealer sells for $35/plug
I stock them (without BMW's name) for $45 per set of 4
--Dan

 

Another outlet for these plugs is http://www.sparkplugs.com/results_cr...EQUP&x=51&y=13

 

Or: http://www.ngkwholesale.com/