Ok here's another `speed equipment' secret..
`Copper Core' spark plugs use 2.2mm diameter STEEL subarc welding wire as the centre electrode, it has about 2 or 3 microns of copper plating on it!
Copper core, pffffft...
It's called `marketing'.....


BTW if you don't believe me, cut one up... I know the guys who made the wire for Champion plugs!

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DrMini- 1970 wasaMatic 1360, Mk1S crank, 86.6HP (ATW) =~125 @ crank, 45 Dellorto (38 chokes), RE282 sprint cam, 1.5 rockers, 11.0:1 C/R.

Quote......."Indexing" of plugs is sometimes done with 2 litre Alfas, but this is because the inlet valve can foul the electrode of some conventional plugs. This potential problem can be avoided using the (expensive, rare) standard Lodge surface discharge plugs. I found no detectable difference or improved life compared with NGKs in any of my Alfas....unquote

and again....from a gun engine builder...

Oh yeah, "spark plug indexing" is real. Where the gap should be oriented will vary from engine to engine, but in general usually you want the open side of the gap facing toward the center or active area of the chamber, and the side electrode backed up against the chamber wall.

Where folks first got thinking about gap orientation: There are engines with built-in clearance problems...aluminum connecting rods, pistons with lots of compression height and/or tight squish volumes, racing outboards etc. In those applications the gap must be oriented in a precise position or it will be mashed or fouled.

And as a byproduct of this minor pain in the ass in spark plug maintenance, what they found was if the plugs are all indexed in the same direction they are much easier and more consistent to read in tuning. Hmm. (An entire book could be written about the dying art of reading spark plugs.) That got them to thinking about orienting the plug for optimum spark and combustion. Then as the years went on, dynos got good enough that this could all be precisely quantified, and yes, it's very real. Small, but real.

...the older the engine design the more it will respond to plug indexing...in other words, the crappier the combustion chamber design, the more primitive the fuel metering system and the more marginal the ignition, the more likely indexing will produce an measurable gain. On the 318 poly V8 I would certainly tend to think so. But on a modern 4-valve head with high-energy ignition and precise fuel metering (EFI) it's not liable to make any difference at all. It will still make plug-reading easier and more accurate however.

Important notes...to index plugs properly you need some copper indexing washers designed for the purpose, available from Moroso and elsewhere. Never use a standard plug gasket on a taper-seat plug, or remove a gasket where there is supposed to be one. Never stack plug gaskets, or over-tighten or under-tighten the plug to get the orientation you want. These practices absolutely WILL alter the effective heat range of the plug, make it impossible to read properly, and undo any benefits accruing from going to all the trouble in the first place. Also, while performing your plug indexing, use a felt tip marketr etc, never use a lead pencil to mark the exterior porcelain. You are drawing a carbon track down the side of the spark plug and thus playing a hilarious practical joke on yourself, hahaha. Hard to believe but I have actually seen people do this.

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"Show me the Mini!"

here are some pics of my plugs
These are my B8EGV race plugs note the smallelectrode, running a bit oily and rich but better rich than lean especially with turbo, see one on the left has a melted electrode (missing) i think i had the timing a little to far advanced oops .

and these are the BP8ES STD plugs.

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100% Pure A Series Turbo
Morris - The Original RedBull Racing

Centre electrode on RH one in 1st pic looks a bit suss...
2nd pic ones look OK to me.

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DrMini- 1970 wasaMatic 1360, Mk1S crank, 86.6HP (ATW) =~125 @ crank, 45 Dellorto (38 chokes), RE282 sprint cam, 1.5 rockers, 11.0:1 C/R.

the brick is in getting its ign conversion, i'm getting a high voltage bosch coil but am not sure about the dizzy, will get the car back 2moro or wed's and have got some split fire's on the way wich were recomended by a mate if i got a better voltage coil when i did the swap. will let you know how it goes with normal plugs and with the splits when i get them some time nxt week.

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68' Morris, 1100,

Willson Automotive
Tasmania's ONLY mini Specialists
(03) 62725056

http://photobucket.com/albums/a323/the_white_one/