I like Glow Devils for most everything.  They have standard or idle bar, long and short.  I prefer the idle bar for pipes.  There are from Sonic Tronics in Pa.  Order on line.  They also have one special for OS engines- replaces type F.

Dave


Addendum:  Plug length is determined by the manufacturer depending on how the head was machined.  Refer to their instructions.  As a general rule I would think .15 and larger would use long.  The .10 may use short.  You might damage it trying to use long.

One of the reasons I ask about reach is that some express a preference for the OS #8 plug in .25 and larger engines.  If I'm not mistaken, OS defines that as a "medium reach" plug ... correct me if I'm wrong!


Dennis
 

Both OS and Enya plugs have always been "medium" reach and why this is no one seems to know. However, based only on my 40/46 VF's, a medium reach is too short while a long reach is a fraction too long but not enough to worry about. Enya at least seem to machine their heads to suit a medium length plug although a long reach with an extra washer fits very well.

Of you don't want to take the heads off to check then I'd use a short or medium plug for the 10 and maybe the 15 while a long reach would be fine in the larger engines. For heat range I'd go with a hot plug but brand is up to you because everyone has their own ideas. Personally I use Taipan plugs.

Are Taipan glowplugs made in Australia?

Yep, they're still made in Australia but by Lion Electronics in Perth, Western Australia.
http://www.tnet.com.au/~lion/Taipan_Glow_Plugs.htm

I use Fox 2 volt longs in engines where they will fit.   I don't race anymore so I don't know how they would be racing.  Back in the day, we used GloBee plugs to race.