Checked spark plugs 2015 Mirage ES about 98700 miles

[Grumpy Bear]

Still thinking of trying
NGK 96355 LFR5AHX Ruthenium HX Plug
Anyone trying yet here?

Ruthenium, yes in a GM Ecotec 2.4 I-4 and GM Ecotec3 4.3 V6. I'm happy. Your milage my vary.

[Fummins]

from big sparkplug



Attachment 26371

Wow, 23 seconds to get to 90kph/55mph!

[Eggman]

Wow, 23 seconds to get to 90kph/55mph!

Must be either green or gray. Reds & blues are faster especially with the valve lash dialed in.

[7milesout]

I run NGK Ruthenium plugs in a few other vehicles in my stable that came with Iridium.

GrumpyBear - What part number NGK Ruthenium plugs are you running in your Mirage?

I ask because I'm looking into it. Just out of curiosity. And I'm finding that the TR5AHX Ruthenium plug has a thread reach of 0.708 inches / 18.0 mm.

However, the NGK 93298 LZFR5BI-11 OEM spark plug has a thread reach of 1.043 inches / 26.5 mm.

I don't know this as a FACT, because I'm not a spark plug design engineer. But if the material volume of the spark plug that is exposed to the combustion chamber is reduced, so will the compression ratio be reduced. What I don't know, is that maybe a spark plug with a shorter thread reach may have some other difference(s) on the electrode end to make up the difference in thread material.

Now again, I'm no expert on this, I've never designed a spark plug. And the numbers I have found for thread reach does come from the internet (not known for always being accurate), so I'll admit I may be wrong.

Thread reach is the thread length from the thread seat (where it bottoms) toward the electrode. If you pull 8.5 mm of length, times the thickness of that threaded wall, times the circumference ... that will make a measurable difference in compression ratio. That "measurable difference" might be very small, but still measurable (scientifically). It might not be felt by the seat of the pants. But I bet a drag strip trap speed would discern the difference. That is, if nothing else within that design of the electrode end of the spark plug makes up for the volume loss of that thread reach.

Lots of problems with my post and research. You may run a Ruthenium spark plug I have not found. I sure don't KNOW what the hell I'm talking about. And the numbers I'm finding may not be 100% accurate.

Assuming I am correct however, this would be the only reason right now that I wouldn't bother with trying a set of Ruthenium plugs. Unless there is one that is perfectly equivalent ... sans the Ruthenium.

Do you have any thoughts on this?

[7milesout]

must be either green or gray. Reds & blues are faster especially with the valve lash dialed in.

f-a-c-t

[Fummins]

GrumpyBear - What part number NGK Ruthenium plugs are you running in your Mirage?

I ask because I'm looking into it. Just out of curiosity. And I'm finding that the TR5AHX Ruthenium plug has a thread reach of 0.708 inches / 18.0 mm.

However, the NGK 93298 LZFR5BI-11 OEM spark plug has a thread reach of 1.043 inches / 26.5 mm.

I don't know this as a FACT, because I'm not a spark plug design engineer. But if the material volume of the spark plug that is exposed to the combustion chamber is reduced, so will the compression ratio be reduced. What I don't know, is that maybe a spark plug with a shorter thread reach may have some other difference(s) on the electrode end to make up the difference in thread material.

Now again, I'm no expert on this, I've never designed a spark plug. And the numbers I have found for thread reach does come from the internet (not known for always being accurate), so I'll admit I may be wrong.

Thread reach is the thread length from the thread seat (where it bottoms) toward the electrode. If you pull 8.5 mm of length, times the thickness of that threaded wall, times the circumference ... that will make a measurable difference in compression ratio. It might not be felt by the seat of the pants. But I bet a drag strip trap speed would discern the difference. That is, if nothing else within that design of the electrode end of the spark plug makes up for the volume loss of that thread reach.

Lots of problems with my post and research. You may run a Ruthenium spark plug I have not found. I sure don't KNOW what the hell I'm talking about. And the numbers I'm finding may not be 100% accurate.

Assuming I am correct however, this would be the only reason right now that I wouldn't bother with trying a set of Ruthenium plugs. Unless there is one that is perfectly equivalent ... sans the Ruthenium.

Do you have any thoughts on this?

Ruthenium:
NGK 96355 Specifications
Center Electrode Core Material Copper
Center Electrode Tip Material Ruthenium
Electrical Terminal Type Non-Removable Nut
Gap Size (IN) .044
Ground Configuration Standard
Ground Electrode Core Material Nickel
Ground Electrode Quantity 1
Ground Electrode Tip Design Dual Fine Electrode - High Ignitability
Hex Size (IN) 5/8
Insulator Height (mm) 50.50
Manufacturer Heat Range 5
Part Number LFR5AHX
Reach (mm) 26.5
Resistance (ohms) 5000
Seat Type Flat
Stock Number 96355
Thread Diameter (MM) 14.00

Oem plug:
NGK 93298 Specifications
Center Electrode Core Material Copper
Center Electrode Tip Material Iridium
Electrical Terminal Type Non-Removable Nut
Gap Size (IN) .044
Ground Configuration Standard
Ground Electrode Core Material Nickel
Ground Electrode Quantity 1
Ground Electrode Tip Design Standard
Hex Size (IN) 5/8
Insulator Height (mm) 50.50
Manufacturer Heat Range 5
Part Number LZFR5BI-11
Reach (mm) 26.5
Resistance (ohms) 5000
Seat Type Flat
Stock Number 93298
Thread Diameter (MM) 14.00

[7milesout]

That 96355 would be the equivalent spark plug. I don't know how you found that.

I might try that one, but it may be another 3 or 4 years.

[Fummins]

I don't know how you found that.

Easy!
I just looked up spark plugs on rockauto.

[7milesout]

Ah yes. Rockauto. I forget about that unless I'm actively looking for parts for myself. It's part of my sourcing routine.