So many different kind of spark plugs! From materials to construction to brands to everything. Where do you start?
Bring on the spark plug debate!
- Thread starter freshcedar
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With what your owners manual tells you to use.
If the ones you are replacing worked well, replace them with the same. They are probably what the owners manual suggest.
Good plugs are good, better plugs are better!
Give us your application or plug number and we can do some digging around.
Give us your application or plug number and we can do some digging around.
The owners manual already gives you the part numbers of what spark plugs to buy for NGK's or Denso, or OEM, at least in my Toyotas.
Unless its my Chevy 5.3L with a spark plug TSB to run iridium spark plugs with a smaller gap (vs plats at .060 gap) then thats a different story. Running Denso Long Lifes in the old LM7.
Or Denso or NGK by default preference. Neither plugs call for antiseize.
That's my "set in stone" opinion unless otherwise.
Unless its my Chevy 5.3L with a spark plug TSB to run iridium spark plugs with a smaller gap (vs plats at .060 gap) then thats a different story. Running Denso Long Lifes in the old LM7.
Or Denso or NGK by default preference. Neither plugs call for antiseize.
That's my "set in stone" opinion unless otherwise.
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My spark plug choices are fairly simple:
I use ONLY NGK or NipponDenso (ND).
From those two brands I use ONLY normal copper core or Iridium based on what was originally installed. I don't fool with platinum plugs anymore. They were cutting edge until Iridium came out and now they don't have any benefit for me.
At present all of my gasoline powered automobiles and motorcycles are using NGK; two with V-Power and two with Iridium.
I use ONLY NGK or NipponDenso (ND).
From those two brands I use ONLY normal copper core or Iridium based on what was originally installed. I don't fool with platinum plugs anymore. They were cutting edge until Iridium came out and now they don't have any benefit for me.
At present all of my gasoline powered automobiles and motorcycles are using NGK; two with V-Power and two with Iridium.
Originally Posted By: FowVay
My spark plug choices are fairly simple:
I use ONLY NGK or NipponDenso (ND).
From those two brands I use ONLY normal copper core or Iridium based on what was originally installed.
This.
My spark plug choices are fairly simple:
I use ONLY NGK or NipponDenso (ND).
From those two brands I use ONLY normal copper core or Iridium based on what was originally installed.
This.
The problem with owners manuals is the specs get outdated as they age. Technology and lubes don't stand still like the manual.
depends... looking for longevity? dirt cheap? "performance"?
If NGK makes a Laser Iridium for the application, I try and use this whenever possible. I have great results with NGK plugs no matter the application. However, for the most part, I stick with the factory plugs. For example, my GF's IS250 specs Denso Iridiums, which are about $11/piece from Sewell. The aftermarket NGK Laser Iridiums are $19/piece. (I would have went with the NGKs in this case however her car is affected by the Carbon-buildup TSIB and I've read Lexus will not do the work if anything other than factory plugs are installed).
With my brother's track-prepped '99 Miata, the factory plugs are nothing special, neither platinum or iridium. Since it is a waste-spark system, I believe it does benefit from NGK's 'Laser Iridium' plugs, that is, they have a platinum pad welded for the ground whereas the regular Iridium IX plugs do not.
With my brother's track-prepped '99 Miata, the factory plugs are nothing special, neither platinum or iridium. Since it is a waste-spark system, I believe it does benefit from NGK's 'Laser Iridium' plugs, that is, they have a platinum pad welded for the ground whereas the regular Iridium IX plugs do not.
If i can get at them right on top, I do try different ones. If it takes an hour to service one cylinder bank I do OEM recommended and leave it be...another thing to address are wires. I think plugs outlast wires these days but its much cheaper to chase down a miss buying plugs than all new wires.
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No debate....Use OEM.
I am with the others, no reason to "start" anywhere, use what is factory...
I will either go full OE or use the NGK equivalent because I think they make the best spark plugs.
I will either go full OE or use the NGK equivalent because I think they make the best spark plugs.
NGK Iridium IX in any vehicle that has a plug available.
I'll start the opposite opinion just for the heck of it.
Start with rebates, look at the plugs that is cheap to try.
Start with your car's ignition system, and use precious metal on both electrodes (double platinum, platinum on one iridium on the other, double iridium, etc) for waste spark, and single iridium or platinum on other types.
Pick the finest cheap to try precious metal plug, and the reduced ignition voltage will pay back in fuel economy and "performance" on butt dyno.
Check them on a regular basis to prevent using them for too long (30k for copper regular, 60k-90k for platinum or double platinum, 120k for iridium, etc). Check more often if you think something is wrong (i.e. insulator cracked, plug loosen out, etc).
Save your old OEM plugs, when in doubt try to put the old plugs back to see if problems are caused by the plugs.
Start with rebates, look at the plugs that is cheap to try.
Start with your car's ignition system, and use precious metal on both electrodes (double platinum, platinum on one iridium on the other, double iridium, etc) for waste spark, and single iridium or platinum on other types.
Pick the finest cheap to try precious metal plug, and the reduced ignition voltage will pay back in fuel economy and "performance" on butt dyno.
Check them on a regular basis to prevent using them for too long (30k for copper regular, 60k-90k for platinum or double platinum, 120k for iridium, etc). Check more often if you think something is wrong (i.e. insulator cracked, plug loosen out, etc).
Save your old OEM plugs, when in doubt try to put the old plugs back to see if problems are caused by the plugs.
Replace the OEM plugs with the exact ones if it is possible. Sometimes the manual will specify to use a certain NGK part number or a certain Denso part number, and in that case, just buy whatever is easier to get. I often find that in Honda and Toyota service manuals.
Sometimes a TSB will be released and tell you to use a different spark plug. In that case, use that plug, and ignore what earlier publications said to use.
With Ford cars, if you can't get the Motorcraft plug, an Autolite plug will do the job. Use a torque wrench and the torque spec in the manual, some Ford engines blow the plugs out of the head if you don't.
If you can't get the OEM plug, usually an NGK works properly.
Sometimes a TSB will be released and tell you to use a different spark plug. In that case, use that plug, and ignore what earlier publications said to use.
With Ford cars, if you can't get the Motorcraft plug, an Autolite plug will do the job. Use a torque wrench and the torque spec in the manual, some Ford engines blow the plugs out of the head if you don't.
If you can't get the OEM plug, usually an NGK works properly.
After taking my last 90k set out of my truck that looked like new...I'm not going to replace spark plugs anymore. I suspect they will make it to 200k before throwing a misfire code.
So my vote is to leave them until they break.
So my vote is to leave them until they break.
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