SJ Plug questions

[227]

I’m running the stock head on my SJ now which uses a B7HS and I’d like to go with solid plugs. I can’t find a B7HS in solid but they do sell BR8HS in solid. I know the R stands for resistor and I think an 8 is a cooler plug, other than that I think they are the same.

1. Can anyone think of a reason why I can’t run the BR8HS’s instead of B7HS? Is a B8 too cold of a plug for an SJ?

2. Also anyone know the difference between a B7HS and a B7HS-10?

 

[Matt_E]

I've been running 8-range plugs in my various SJ motors for as long as I can remember.
I believe later model SJ's specified the 8-range.
I am no expert, but I (and plenty others) run BR8ES without issues.

The B7HS-10 is simply a B7HS plug pre-gapped to .10

 

[227]

Thanks Matt, that makes sense. I ran BR8ES's in my SJ also when I had an aftermarket head, except I thought the higher number was a cooler plug. I prefer the hotter plug. I just wanted to be sure before I put in a $50 order for plugs

 

[Matt_E]

put in a $50 order for plugs

I need to do that. I hate the screw-on tipped plugs, and my local supply of solid tops went out of business.

 

[227]

Club plug has BR8HS-solids for $2.06 ea

http://www.clubplug.net/cgi-bin/search.cgi

I know they also sell BR8ES-Solids also

 

[tor*p*do]

Club plug has BR8HS-solids for $2.06 ea

http://www.clubplug.net/cgi-bin/search.cgi

I know they also sell BR8ES-Solids also

club plug is cool!
I got a set of plugs for my Acura
and saved enough to get a free box of BR8ES solid tops
for the same money as buying local!

 

[Matt_E]

Nice, thanks!

 

[JetManiac]

Solid tips are the only way to go especially in salt water!

I have always run 8's also.

 

[#ZERO]

Clubplug has a lot of hard to find plugs with great prices.

I like using the non-resistor 2-stroke NGK racing plugs with the solid tops.

 

[227]

I like using the non-resistor 2-stroke NGK racing plugs with the solid tops.[/QUOTE]

Non resistor advantage? plug number?

 

[Woody]

You've got the heat range reversed. NGK plugs have lower numbers for colder plugs.

no...you're wrong. here is the chart:
http://runryder.com/helicopter/gallery/1170/ngksparkplug_.jpg

 

[Woody]

i use bpr8es...apparently it'll fire anything.

 

[Matt_E]

no...you're wrong. here is the chart:
http://runryder.com/helicopter/gallery/1170/ngksparkplug_.jpg

You're correct - I got it screwed up.
Directly from NGK:

The spark plug heat range has no relationship to the electrical energy transferred through the spark plug. The heat range of a spark plug is the range in which the plug works well thermally. The heat rating of each NGK spark plug is indicated by a number; lower numbers indicate a hotter type, higher numbers indicate a colder type.

 

[tor*p*do]

Non resistor advantage?

None
resistor plug just prevents interference with the stereo in the vehicle
shouldnt be a problem in a standup!!!
if running the non-resistor plug, I have heard you should
go with resistor plug caps like NGK screw on caps

 

[Woody]

edit: double post, sry

 

[#ZERO]

I like using the non-resistor 2-stroke NGK racing plugs with the solid tops.[/QUOTE]

Non resistor advantage? plug number?

I'm using the longer version spark plug and I don't think they have the short reach in this type.

Resistor 2-Stroke Racing Plug
BR8EG-SOLID
#3992

Non-Resistor 2-Stroke Racing Plug
B8EG-SOLID
#3997

The non resistor plugs deliver more amperage with less voltage and are more suited for marine use or racing applications. Resistor plugs were mainly designed for radio suppression and emi interference problems. These plugs use more copper inside so they're just a bit more costly but they are specifically designed for the 2-stroke engine. They're made for racing and have a deep seated copper core with a wider heat range which is more resistant to fouling. Also they have the fine-wire center electrode which provides better sparking and enhanced ignitability.

 

[StandupEd]

For surf I use B6HS. Stock shaved head. Especially in pacific water temps. For me average 55-58 degrees. I buy plugs by the box of tens and like to have several boxes available especially if you or your buddy swamps. Think about how much is spent just on gas? After a ride pull your plugs and compare with a buddy running 8’s yours will be crispy and brown, the 7 or 8’s will be black and slimy sometimes even frothy foamy. In surf how long are you ever WOT? Cool air, cool water. Biggest problem is staying on temp. Maybe in Florida in July, in small waves doing more high speed Moto surf /racing style ridding the 8’s would be appropriate.

 

[227]

For surf I use B6HS.

B6HS aren't available in solids which was the original intention of this thread. Thanks for the input.

 

[StandupEd]

Opps, my bad, incomplete post. What I do for the caps is unscrew them, then mildly , crush, deform the plug threads with a small vise grip, then I screw the cap back on. If you have some old plugs lying around can use those for practice. I also put in new plugs frequently so the caps never seem to loosen up. I’d love to run solid tips too, but for me the hotter plug seems to foul a lot less. Especially for the constant water ingestion of surf ridding.

 

[Matt_E]

It's important to note that a "hotter plug" has the same spark energy as a "colder" plug. Thermal conduction of the plug body is different.
A hotter plug doesn't burn anything any hotter than a colder plug. It will warm the engine up a bit more by preventing heat conduction a bit more than colder plugs.
You could achieve the same effect by restricting cooling a bit more.