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well, as per hattech-v asking..
I'm no plug tech, but I know the basics of choosing the right plug and deciding if I have to go with different numbers or not.
There is no recommended/best plug for the b-series.. it's highly dependent on your setup.
A bigger spark or whatever doesn't really affect combustion (remember those display things at n1 that compare two similar plugs?
A better plug with a bigger has better lifespan.. period. The spark only ignites the fuel air mixture, and that's it.. how the mixture explodes is what makes the power. Of course, a built engine that has a very aggresive fuel timing curve, which is why you notice that they run near stoich at idle and low revs, then drastically increase as the revs climb along with the ignition timing..
Since the so called performance plug can spark more, so it can last longer as it's materials get worn out, it can still generate adequate spark.
There's a lot of factors like plug gap, etc. etc. , but the simplest one I use is this... look at plug colour, and decide.. mine when running stock regulator is no 22 in the list (the whitish tip is very noticable, while bumping up the pressure on the regulator resulted in no 14, at best, with the colour being the stock light brown colour.
http://www.dansmc.com/Spark_Plugs/Spark_Plugs_catalog.html
see color... too lean? add fuel on the regulator...
still no? use hotter/colder plugs 1 rating below the current one. Once you get them to run brownish colour, you've got the best plug for your setup. (give it a spin before checking, make sure you hit max rpm a few times, and accelerate smoothly, so you don't mess up the plug colour when you take it out.) If you want to check at a particular rpm point, just retain that point for a while, stop, and take out plugs to check. Usually lower rpms will show slightly lean or rich (depending on your tune) but that's not for deciding plugs, since that's not where they will see max temp in the combustion chamber.
For most NA applications.. just keep bumping up pressure until you get that brownish colour.. if not, you're probably using the wrong rating. Sometimes, at the max rpm point, 4-5bar might even run nicely, but idle will suck, so consider that your baseline at max as 4-5bar for regulator, Then, detune the fuel enrichment using any form of engine management you like. (with a wideband, so you don't detune too much and blow up your engine)..
Added: It might seem obvious to me, but just to note that if your plugs are fouling at max rpm, lower the pressure until you can get that brown color.. For B-series hondas.. this is so common it's no longer a theory or not... 3/3.5 bar is best for non built engines!
I'm no plug tech, but I know the basics of choosing the right plug and deciding if I have to go with different numbers or not.
There is no recommended/best plug for the b-series.. it's highly dependent on your setup.
A bigger spark or whatever doesn't really affect combustion (remember those display things at n1 that compare two similar plugs?
A better plug with a bigger has better lifespan.. period. The spark only ignites the fuel air mixture, and that's it.. how the mixture explodes is what makes the power. Of course, a built engine that has a very aggresive fuel timing curve, which is why you notice that they run near stoich at idle and low revs, then drastically increase as the revs climb along with the ignition timing..
Since the so called performance plug can spark more, so it can last longer as it's materials get worn out, it can still generate adequate spark.
There's a lot of factors like plug gap, etc. etc. , but the simplest one I use is this... look at plug colour, and decide.. mine when running stock regulator is no 22 in the list (the whitish tip is very noticable, while bumping up the pressure on the regulator resulted in no 14, at best, with the colour being the stock light brown colour.
http://www.dansmc.com/Spark_Plugs/Spark_Plugs_catalog.html
see color... too lean? add fuel on the regulator...
still no? use hotter/colder plugs 1 rating below the current one. Once you get them to run brownish colour, you've got the best plug for your setup. (give it a spin before checking, make sure you hit max rpm a few times, and accelerate smoothly, so you don't mess up the plug colour when you take it out.) If you want to check at a particular rpm point, just retain that point for a while, stop, and take out plugs to check. Usually lower rpms will show slightly lean or rich (depending on your tune) but that's not for deciding plugs, since that's not where they will see max temp in the combustion chamber.
For most NA applications.. just keep bumping up pressure until you get that brownish colour.. if not, you're probably using the wrong rating. Sometimes, at the max rpm point, 4-5bar might even run nicely, but idle will suck, so consider that your baseline at max as 4-5bar for regulator, Then, detune the fuel enrichment using any form of engine management you like. (with a wideband, so you don't detune too much and blow up your engine)..
Added: It might seem obvious to me, but just to note that if your plugs are fouling at max rpm, lower the pressure until you can get that brown color.. For B-series hondas.. this is so common it's no longer a theory or not... 3/3.5 bar is best for non built engines!
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