Spark plugs
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Many subjects will have been discussed before. Please try the search function before starting a new thread.
Check in the Know Your 2 as the information you need may already be there.
Important ! - Please make your topic title as descriptive as possible . titles with just "help" generally dont get as many answers as a title that points to the problem
Spark plugs
Can anyone shed some light on what plugs to run, cars expected to make 380-390, I've currently got 1 grade cooler copper plugs but that was on my previous setup 330 and now going bigger so just wondering what works with higher boost say 1.8bar
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MR2DI4
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Re: Spark plugs
Personally wouldn't run copper plugs, you need a fine electrode to minimise the Voltage to give you a spark.
Would still be running iridium or platinum if it was me.
The peak Voltage required to jump the spark gap goes through the roof as the boost increases and that just stresses out any insulation.
Just jump a temperature range or two, you cannot really go that wrong with running something colder.
Would still be running iridium or platinum if it was me.
The peak Voltage required to jump the spark gap goes through the roof as the boost increases and that just stresses out any insulation.
Just jump a temperature range or two, you cannot really go that wrong with running something colder.
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TonyleFrog
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Re: Spark plugs
The stock NGK plug is BKR6EP-8 where
BK = Thread 14mm, Pitch 1.25mm, Hexagon 16mm
R = Resistor type
6 = Heat Range
E = Thread reach 19mm
8 = Plug gap 0.8mm
I use BKR7EIX (NGK code 2667)
IX = Fine wire iridium centre electrode 0.6mm
Same plug gap as above
Iridium electrodes/tips last a lot longer than copper, so the overall cost works out about the same.
I'm nowhere close to running 1.8 bar on my car so one grade colder is quite enough for me.
You could try sticking with (a new set of) 7s when you upgrade.
A visual inspection will immediately confirm whether you need to go to 8s.
If you do, you'll only be writing off around £40. Less than a tankful of the go juice.
ETA. I've just had a look at NGK's technical pages.
https://www.ngk.com.au/technical_info/m ... rformance/
They suggest as a rough guide selecting one heat range colder for every 75-100 hp added.
BK = Thread 14mm, Pitch 1.25mm, Hexagon 16mm
R = Resistor type
6 = Heat Range
E = Thread reach 19mm
8 = Plug gap 0.8mm
I use BKR7EIX (NGK code 2667)
IX = Fine wire iridium centre electrode 0.6mm
Same plug gap as above
Iridium electrodes/tips last a lot longer than copper, so the overall cost works out about the same.
I'm nowhere close to running 1.8 bar on my car so one grade colder is quite enough for me.
You could try sticking with (a new set of) 7s when you upgrade.
A visual inspection will immediately confirm whether you need to go to 8s.
If you do, you'll only be writing off around £40. Less than a tankful of the go juice.
ETA. I've just had a look at NGK's technical pages.
https://www.ngk.com.au/technical_info/m ... rformance/
They suggest as a rough guide selecting one heat range colder for every 75-100 hp added.
If you're not living life on the edge, you're taking up too much room!
HM wrote: TonyleFrog aka "The Fog Penetrator"
HM wrote: TonyleFrog aka "The Fog Penetrator"
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MR2DI4
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Re: Spark plugs
Running the same 7 iridium's in mine but will go back to the stock 6 Platinum plugs if they ever need changing, got a set already new in the boxes back from the days they were much cheaper.
Cannot recall problems running colder plugs even in a two stroke. I noticed one day a guy running like a 10 or 11, the main reason I think on reflection is that it increased the compression ratio, then again 100 octane race fuel used to stuff my plugs by killing the insulation until the spark took an alternative route so maybe running the insulator cooler prevented whatever it was forming in the extreme heat of an air cooled engine.
As long as MR2 is not burning oil, the cooler plugs will be fine. The temperature of the insulator is supposed to have an effect on the ignition process but generally speaking there are more important things to worry about. A plug that is to cold is not going to suddenly kill your engine.
Cannot recall problems running colder plugs even in a two stroke. I noticed one day a guy running like a 10 or 11, the main reason I think on reflection is that it increased the compression ratio, then again 100 octane race fuel used to stuff my plugs by killing the insulation until the spark took an alternative route so maybe running the insulator cooler prevented whatever it was forming in the extreme heat of an air cooled engine.
As long as MR2 is not burning oil, the cooler plugs will be fine. The temperature of the insulator is supposed to have an effect on the ignition process but generally speaking there are more important things to worry about. A plug that is to cold is not going to suddenly kill your engine.
Re: Spark plugs
It's just had a fresh forged engine rebuild and I'm running 50/50 water meth injection
