Iridium Spark Plug Gap

[fastfraser]

Hi All I'm installing the DCPR8 Iridium plugs in my 2011 RTS and just want to check the gap to be sure its right . Anyone know the correct gap ?:dontknow:

 

[BajaRon]

If you're gapping true Iridium spark plugs do not use a standard gap tool. The Iridium center electrode is very hard, and very brittle. If you put any pressure on it you will fracture it for sure.

 

[BLUEKNIGHT911]

GAP TOOL

If you're gapping true Iridium spark plugs do not use a standard gap tool. The Iridium center electrode is very hard, and very brittle. If you put any pressure on it you will fracture it for sure.

Thanks Ron, this is great advice .............except for the missing part...................What tool should you use ? ? ?......thanks Mike:thumbup:

 

[fastfraser]

If you're gapping true Iridium spark plugs do not use a standard gap tool. The Iridium center electrode is very hard, and very brittle. If you put any pressure on it you will fracture it for sure.

Hi Ron

I bought the plugs from you and they have sat on my workbench for awhile. I'm going to install them this week and just wanted to check the gap . What is the correct gap and how should I check it so as to not damage the tip ?

 

[BajaRon]

What am I.. The Answer Man!? You're supposed to be bugging Scotty for this follow up stuff.

I tell most people to just install the Iridium plugs I sell with the gap they come with to avoid breaking the center electrode.

But here are 2 good tools for adjusting the gap on Iridium spark plugs. Of course they will work on most any adjustable gap plugs as well. As long as you are careful, either will work well. The Iridium center is fragile. Once you fracture it, even the slightest bit, that plug is done.

If you're going to adjust your spark plug I recommend .8mm or .032"

This is what NGK says;

"The re-gapping of fine wire spark plugs that have very small diameter platinum or iridium alloy electrodes is not recommended due to the risk of damaging the electrodes. Virtually all NGK spark plugs are set to the correct gap for the catalogue applications at the point of manufacture."

This is the Correct way to do it

This is the WRONG way to do it.

This is what you ABSOLUTELY DO NOT WANT TO DO! This is a wedge tool which leverages between the center electrode and the ground electrode. It will break your platinum or iridium plug every time. It works fine for standard center electrode plugs, but you'll be crying in your soup if you do this with an Iridium plug.

Now ask Scotty what the book recommends.... hyea:

 

[AbNormy]

As long as the cardboard tube they come with isn't smashed they should be ok, no?

Sent from my HTCONE using Tapatalk 2

 

[NancysToy]

This is the kind of tool I prefer.

Correct gap in English units is 0.028" - 0.031".

 

[BajaRon]

This is the kind of tool I prefer.

Correct gap in English units is 0.028" - 0.031".

4 reasons I recommend .8mm or .032" are"

1- My custom race wire set has much less resistance (50-150 ohms per foot as apposed to the OEM wires which are 1,500~3,000 ohms per foot) so that there is greater spark energy delivered to the spark plug to jump the gap.

2- It takes less spark energy to jump the gap on an IX Iridium than even the OEM Laser Welded Iridium spark plug.

3- Most spark plug gap recommendations take into account electrode wear (which increases gap). Since there is virtually zero wear on an IX Iridium spark plug there does not need to be an initial fudge factor in the gap setting.

4- .032 isn't that much over the higher OEM setting. A wider gap will give you better flame propagation (just a fancy term for better fuel ignition) and with my wire set and IX Iridium spark plugs you will have more than enough energy to jump that gap with a strong spark

Scotty's recommended tool was developed by racing to quickly and accurately gap multiple spark plugs (V-8). They are relatively easy to use and like Scotty says, they do a great job if used properly (which can be said of any tool).

These normally run in the $60.00 range but you can get them for just over $30 at Jegs. http://www.jegs.com/i/Accel/110/380...&cagpspn=pla&gclid=CNuU26Wm9rgCFcbm7Aod6mMAfg

 

[NancysToy]

I like the higher gap with iridium plugs, too. A wide gap gives more spark, but too wide can offer excess electrical resistance. As Ron said, his plugs offer less resistance than a standard plug, so the gap can be kept to the wide side of the spec. The iridium plugs, like platinum plugs, don't wear away fast and open the gap too far, so you can start the gap at maximum, without it opening up excessively as time passes.

 

[fastfraser]

Thanks Ron & Scotty

I don't plan on re-gapping the plugs but because they have sat for a bit on my work bench, I just want to make sure the gap is correct before the install .

 

[BajaRon]

Thanks Ron & Scotty

I don't plan on re-gapping the plugs but because they have sat for a bit on my work bench, I just want to make sure the gap is correct before the install .

Not a bad idea to at least check gap. I usually have no idea what the skill level is of customers purchasing these wire/plug sets. So I try to err on the simple side and just recommend installation without checking or setting the gap. I figure the experienced will simply ignore my suggestion and do what they want anyway.

 

[SNOOPY]

What am I.. The Answer Man!? You're supposed to be bugging Scotty for this follow up stuff.

I tell most people to just install the Iridium plugs I sell with the gap they come with to avoid breaking the center electrode.

But here are 2 good tools for adjusting the gap on Iridium spark plugs. Of course they will work on most any adjustable gap plugs as well. As long as you are careful, either will work well. The Iridium center is fragile. Once you fracture it, even the slightest bit, that plug is done.

If you're going to adjust your spark plug I recommend .8mm or .032"

This is what NGK says;

"The re-gapping of fine wire spark plugs that have very small diameter platinum or iridium alloy electrodes is not recommended due to the risk of damaging the electrodes. Virtually all NGK spark plugs are set to the correct gap for the catalogue applications at the point of manufacture."

This is the Correct way to do it

This is the WRONG way to do it.

This is what you ABSOLUTELY DO NOT WANT TO DO! This is a wedge tool which leverages between the center electrode and the ground electrode. It will break your platinum or iridium plug every time. It works fine for standard center electrode plugs, but you'll be crying in your soup if you do this with an Iridium plug.

Now ask Scotty what the book recommends.... hyea:

There it is...thanks. Lol


.

 

[DaniBoy]

Sorry, as I know this is an old thread, but Ron, I could’ve sworn that you told me that .034” was a good gap for the 8’s when I bought them last week, so that’s what I did yesterday. I used flat feeler gauges to test adjustments. I’m just confused, because here you’re saying .032”

 

[BajaRon]

Sorry, as I know this is an old thread, but Ron, I could’ve sworn that you told me that .034” was a good gap for the 8’s when I bought them last week, so that’s what I did yesterday. I used flat feeler gauges to test adjustments. I’m just confused, because here you’re saying .032”

Yes, old thread. If you are using carbon core wires I recommend leaving spark plugs at the original gap of .031". But if you are installing a good set of continuous wire core wires. Then opening up the gap to .034" will give you quicker starts, better throttle response, and probably a bit more HP, though not enough to notice.