performance spark plug?


New Member
Oct 26, 2008
Australia Brisbane
Hey guys im posting this because i bought the otherday a NGK B6HS thinking it was a better plug for performance but i see on the zbox website they say the NGK R7-HS spark plug is better for performance.
Has anyone used 1 of these plugs? are they better?
Another question who has upgraded the lead going from the CDI to the sparkplug with just a lead from a automotive store?
If so what did u get and can u fell a difference?


New Member
Jun 23, 2008
Longmont, CO
I too replaced everything at once, so who knows exactly which one made the difference. I do know that the automotive wire has already started giving me fits, so I just used a piece of coax cable (cable tv) and soldered the connector end to it and slipped the boot on. Works great. probably will interfere with electronic speedos and the like though. Hopefully it doesn't give my gps fits.


New Member
Mar 21, 2008
Treasure Coast, Florida
The spark plug wire can be had at MOST auto parts suppliers. Just ask them for a coil/ distributor wire. The Auto zone here took me to the back and let me pick a length and color as they had them hanging on the wall........

The B6HS is a good selection for the plug...........


New Member
Nov 16, 2008
new york city
Im no expert on these little engines, but I do know that if your mixture is a little lean and then you get a hotter plug. It could burn a hole right through the piston. So you would have to monitor the plug checking it for the right color light brown.
Sep 20, 2008
Clearwater, FL
On my first build, (August last year), I went out looking for a replacement plug.

Having messed around with boats quite a bit, I knew the older Evinrude outboards ran on a 24:1 fuel/oil ratio.

I went to West marine and looked up a 1965 10HP twin...the recommended plug NGK B6HS.

I have been using them since, and they work great!

About a month later I joined this forum and saw all of the recommendations about replacing the plug wire. I'm sure it's a good idea although I haven't had a problem yet with the Wang-Chung plug wire...which means nothing because I haven't been able to put any real miles on a MB. Lots of run time, (hours), up and down our dead end street; stop/start, trying to wear out clutches, but no sustained RPM trips.

Automotive plug wires are not the same...I'm guessing that carbon core resistor wire would not be a good idea? These ignition systems are low voltage.

I'm thinking the ideal replacement plug wire should be made from automotive racing wire that is intented for use with a magneto. This is purchased by the foot and the tight fitting boots, (that snap over the threads), are available as well. This is plug "wire" not plug pencil lead. This is what I will use when the time comes.



New Member
Feb 21, 2009
Pacific Northwest
Would it be the same thing if you put an NGK BR7HS instead of a NGK BR6HS? because looking around I accidentally happened to buy the 7 instead of the 6. it just runs hotter right??? Oh yeah and would running that plug on my 25cc mess it up?
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New Member
Jul 21, 2008
Adelaide Australia
NGK B6HS is the way to go for great starting point, you cant go wrong with this plug, you can change plug heat range depending on the the circumstances for fine tuning, I make up all my own leads using nothing but MSD parts, its what I use in all my race engines & simply custom make them up to suite the MB set ups, overall it makes a very noticable diffrence, not able to show Dyno sheet to prove the diffrence though, this will come shortly

I am working on something very intresting in regards increasing the spark side of things, if it works like I beleive it should its going to be a ripper of a set up! you will love it




New Member
Sep 27, 2008
Excelant points all round, I to replace plug/lead and cap and the differance is very noticable.

For the plug cap I use NGK LD05F. The writings on the cap say: 66F and 5K Ohms
Anyone know if this is the correct plug cap ?

Plug lead is straight out copper plug lead I bought a roll from auto electrician, it is a very much thicker copper strands than the standard kit's supplied which feels soft like kats whiskers. I don't think it is actually proper spark plug lead.

As for the spark plug which is my real question, I always thought for some reason it's
NGK BP6HS, but you guys have stated NGK B6HS,
should I change plug immediately or is this ok ?


Norco John

New Member
May 26, 2009
Brookston, IN
Question about heat ranges:
Are lower numbers hotter, and higher numbers colder, and is this consistent from maker to maker? F'instance, is a Champion L78 hotter than a L82?


New Member
May 22, 2009
A platinum plug is more resistent to fouling out than the cheaper steel plugs. Platinum doesnt oxidize so easily when the electrical arc goes across. Maybe carbon builup is a better description........platinum just plain doesnt corrode as easily as steel.
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