Spark Plug Data Base

Awafrican said:
Gap size: 0.026" - 0.032"| Preferred gap is between 0.026" - 0.028"
for you those who gap in mm: 0.66mm - 0.71mm
Click to expand...

Actually according to the gen2 shop manual:
Spark plug tightening torque 10-14 N-m (102-142 kgf-cm, 89-123 in-lbf)
Spark plug gap
Standard:L 0.60-0.80 mm (0.024-0.031 in)
New spark plug (reference): 0.60-0.70 mm (0.024-0.027 in)

Have the specs changed over time? What is the source for your original walues?
 
John said:
Actually according to the gen2 shop manual:
Spark plug tightening torque 10-14 N-m (102-142 kgf-cm, 89-123 in-lbf)
Spark plug gap
Standard:L 0.60-0.80 mm (0.024-0.031 in)
New spark plug (reference): 0.60-0.70 mm (0.024-0.027 in)

Have the specs changed over time? What is the source for your original walues?
Click to expand...
To my knowledge they have not changed, source of information is trial and error from tuners and the community this is the recommended gap that I believe all tuner will recommend, unless they're trying something unique on an individual basis.
 
John said:
Actually according to the gen2 shop manual:
Spark plug tightening torque 10-14 N-m (102-142 kgf-cm, 89-123 in-lbf)
Spark plug gap
Standard:L 0.60-0.80 mm (0.024-0.031 in)
New spark plug (reference): 0.60-0.70 mm (0.024-0.027 in)

Have the specs changed over time? What is the source for your original walues?
Click to expand...

The Gen1 and Gen2 plugs are different part numbers, but the same plug, other than the gap was tightened to 0.028 from 0.031 going to the Gen2's. Both are made by NGK.

Edit: I don't think the spec itself changed. I should verify in a speed6 or Juan manual later.
 
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GCPhotographers said:
Trying out the Autolite Iridiums XP5263:1 Step Colder
Wish me luck.
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I didn't post in a while but these suck. Two month after install, I had to change them again...right around my zzb. I've been running ngk 1 step ever since. I am looking for 2 but we will see especially how hot it gets here....I think colder plugs with help with the assist of e85 and MAYBE meth

Another note, rockauto is the cheapest overall outside amazon for the ngk 1 step
 
GCPhotographers said:
I didn't post in a while but these suck. Two month after install, I had to change them again...right around my zzb. I've been running ngk 1 step ever since. I am looking for 2 but we will see especially how hot it gets here....I think colder plugs with help with the assist of e85 and MAYBE meth

Another note, rockauto is the cheapest overall outside amazon for the ngk 1 step
Click to expand...
i just got a 2012 speed 3 with 71k on it and i planning on driving it from Seattle to LA this summer when the only mod i have is an AEM intake that came on the car and an access port that i just got (debating on fuel pump internals) should i go with the Colder or the stock heat NGKs?
 
schmidtyty said:
i just got a 2012 speed 3 with 71k on it and i planning on driving it from Seattle to LA this summer when the only mod i have is an AEM intake that came on the car and an access port that i just got (debating on fuel pump internals) should i go with the Colder or the stock heat NGKs?
Click to expand...

With what you have, stock is fine
 
schmidtyty said:
i just got a 2012 speed 3 with 71k on it and i planning on driving it from Seattle to LA this summer when the only mod i have is an AEM intake that came on the car and an access port that i just got (debating on fuel pump internals) should i go with the Colder or the stock heat NGKs?
Click to expand...
Stay stock heat range plugs, I use NGK these days also what my tuner (freektune) recommends. Also get the fuel pump internal upgrade that should be the first upgrade on this platform especially on the gen2 prior to starting any performance modifications. But I digress as this is a sparkplug thread.

Sent from my SM-N910W8 using Tapatalk
 
Some people say the step colder NGK plugs, 6510's are being discontinued, some they're just backordered right now.

has anyone ever used these NGK 90543 ILTR7E9 Laser Iridium Plug, or know any reason why we couldn't? https://www.ngk.com/product.aspx?zpid=40118



They're step colder in the laser iridium series. (6510's are simply iridium) I can't find mention of them anywhere on the forums. The laser iridium series is what the OEM plug (SILTR6A7G 95369) and NGK ILTR6A-8G (3787) are part of. I have not seen a step colder laser iridium plug mentioned anywhere. I'm not here to debate which heat range plug to use, just if your tuner or yourself decides step colder, would these be an alternative to 6510's?

I found them using the NGK advanced look up tool and entering the data found from the 3787 and 95369, just one heat range colder (higher heat range is a colder plug. so 7 is a colder plug than stock 6) https://www.ngk.com/search.aspx?ptn=Spark+Plug&data=13:14mm|16:Tapered|29:Yes|15:25mm+(1")|14:5/8"+(16mm)|19:Solid|180:ISO|21:Iridium|20:Fine+Wire|24:Platinum|23:Standard|298:NGK|18:7&s=1#results

What's also interesting the number of plugs if you enter the data directly from the 3787. 2 other plugs come up that I can find no mention of people using. https://www.ngk.com/search.aspx?ptn=Spark+Plug&data=13:14mm|16:Tapered|29:Yes|15:25mm+(1")|14:5/8"+(16mm)|19:Solid|180:ISO|17:.031"+(0.8mm)|21:Iridium|20:Fine+Wire|24:Platinum|23:Standard|298:NGK|18:6&s=1#results

Are there differences in these plugs I'm not seeing? Different part # for all 3, but same price. Are these additional options for stock heat range laser iridium plugs?
 
mangosmoothie said:
has anyone ever used these NGK 90543 ILTR7E9 Laser Iridium Plug, or know any reason why we couldn't? https://www.ngk.com/product.aspx?zpid=40118
Click to expand...

I've never found a laser iridium plug that said that it fit our cars. I'm not finding anything of the sort with this one, either. The problem with a lot of these random plugs is that even if they appear to fit and are the same size and thread pitch, sometimes they can be slightly shorter/longer, or have other dimensional differences. I think the only way to find out is to order one and see what you get.

Personally I can say I never had any issues with running the OEM plugs at ~360-370 whp in my pu on 2:10 in-tank methanol or E33. They definitely ran hot based on where the annealing mark ended up after hard usage, but I still got 70k out of my first set and another 40-50k out of my second set with no issues and never had any tuning issues with them. I still recommend the OEM plugs for most people, especially in a daily driven application where unless you go WOT frequently, the colder plugs will carb up fast and cause misfires.
 
Awafrican said:
This is a database for spark plugs which have a heat range of stock / 1 / 2 stages colder than stock. If I'm missing anything let me know and I'll update

MSO Spark Plug Database

Gap size: 0.024-0.027" (or smaller where required)
for you those who gap in mm: 0.60-0.70mm

Type and Specs on DISI 2.3L Spark Plugs: 14mm; 5/8 hex; 25mm reach; projected tip; resistor plug

Heat Range Conversion Chart
HKS 25 30 35 40 45 50 52.5 55
DENSO 16 20 22 24 27 31 32 34
NGK 5 6 7 8 9 10 10.5 11
Spark Plug Manf & Part Numbers

Denso Iridium​
  • itv-20: Stock heat range
  • itv-22: 1 stage colder heat range
  • itv-24: 2 stage colder heat range
  • itv-27: 3.5 stage colder heat range
NGK IX Iridium

  • NGK SILTR6A7G (95369) Stock Heat Range - Gen2 OEM Part 0.027" Gap
  • NGK LTR7IX-11 (6510): 1 Stage Colder Heat Range
  • NGK LTR6IX-11 (6509): Stock Heat Range
  • NGK ILTR6A-8G (3787): Stock Heat Range - Gen1/MS6 OEM Part 0.032" Gap
NGK Ruthenium HX
  • NGK LTR6BHX (90495) Stock Heat Range

HKS​
  • 50003-M35LF 'Mazda MZR Engine': Mazda 3, Mazda 6, MX-5 '06 7 $22.97ea. - 1 Stage Colder Heat Range
  • 50003-M40LF 'Mazda MZR Engine': Mazda 3, Mazda 6, MX-5 '06 8 $22.97ea. - 2 Stage Colder Heat Range
Torque Master Spark Plugs​
  • SVTP8BR: Stock Heat Range
  • SVTP7YR: 1 Stage Colder Heat Range
Autolite Iridium​
  • Autolite Iridiums XP5364: Stock Heatrange
  • Autolite Iridiums XP5263:1 Step Colder
Copper Plugs

NGK Copper Plugs​
  • LZTR4A-11 (5306)
  • LZTR5A-13 (4306)
  • BKR7E
Click to expand...

Awafrican I have made a few updates/ additions to the list. I believe this is a better representation of the modern part numbers and specifications.
 
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John said:
Actually according to the gen2 shop manual:
Spark plug tightening torque 10-14 N-m (102-142 kgf-cm, 89-123 in-lbf)
Spark plug gap
Standard:L 0.60-0.80 mm (0.024-0.031 in)
New spark plug (reference): 0.60-0.70 mm (0.024-0.027 in)

Have the specs changed over time? What is the source for your original walues?
Click to expand...
They were revised when the gen2 was released
Awafrican said:
To my knowledge they have not changed, source of information is trial and error from tuners and the community this is the recommended gap that I believe all tuner will recommend, unless they're trying something unique on an individual basis.
Click to expand...

VTMongoose said:
The Gen1 and Gen2 plugs are different part numbers, but the same plug, other than the gap was tightened to 0.028 from 0.031 going to the Gen2's. Both are made by NGK.

Edit: I don't think the spec itself changed. I should verify in a speed6 or Juan manual later.
Click to expand...

The spec did change, however I'm not entirely sure if Mazda superseded the old part numbers with the new one. None the less I think we can all agree that the a plug that comes at .027" is the better choice regardless or generation. I have attached the related page in gen2 manual for reference.
Mazdaspeed spark plug manual.jpg
 
What kind of life are you guys getting out of plugs these days? I've been going through them every 8-10k-ish these days. There's always a point where I can feel shit starting to feel rougher, I go and pull the plugs, and find that the gap has gone wide and that the plugs are clearly done. The last set of was a set of stock heat range Autolites.... they lasted seven months. I ran ITV-22s for years prior and may go back.
 
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I used the NGK Ruthenium HX (LTR6BHX). They claim to be longer lasting in high heat turbo/super charged engines with ‘high ignitability’.

I’d be interested to hear if any of you with modified engines try them out and what you think.

They come pre-gapped at 0.032. I assumed that was OE and didn’t realise all of you are recommending to gap less. Should I reduce the gap even though I’m still stock?
 
jsilva said:
I used the NGK Ruthenium HX (LTR6BHX). They claim to be longer lasting in high heat turbo/super charged engines with ‘high ignitability’.

I’d be interested to hear if any of you with modified engines try them out and what you think.

They come pre-gapped at 0.032. I assumed that was OE and didn’t realise all of you are recommending to gap less. Should I reduce the gap even though I’m still stock?
Click to expand...

Yes otherwise there would be a "if you're stock gap to this" gap listed
 
jsilva said:
I used the NGK Ruthenium HX (LTR6BHX). They claim to be longer lasting in high heat turbo/super charged engines with ‘high ignitability’.

I’d be interested to hear if any of you with modified engines try them out and what you think.

They come pre-gapped at 0.032. I assumed that was OE and didn’t realise all of you are recommending to gap less. Should I reduce the gap even though I’m still stock?
Click to expand...
There's people that have had the tips fall off.

I wouldn't risk running them.

I added it to the database in my suggested update, as well as listing the revised gap range, but that post seems to be ignored.

I thought about adding a note regarding that, but decided against it.
 
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