What do you guys think about this? They didn't say specifically if you were to do this radiusing yourself, or what, but it seemed interesting. I know that benefits pretty much will be nil, but it'd be a free mod for possibly better combustion if I don't screw it up. Ever heard of this? Like on our NGK plugs that most of us use, take a file or something and instead of having the plug tip squared off. Anyone know what I'm vaguely talking about?

Also, what plug gaps are you guys using and with what coils? I'm just doing some thinking, not actually going to spend money on anything currently... I'm using the Bosch Blue coil right now, but someday in the future, if whatever ignition setup I use needs a regular style coil, I think I'm going to use the MSD Blaster2 coil which seems to go over well with everyone who I've heard of using it.
--
Kyle - '68 142? - Oregon Volvo Tuners?

When using tunescopes high plug voltages are always caused by worn rounded centre eletrodes and poor leads. Refile electrodes or fit new plugs and watch voltage resistance drop dramatically. there is nothing to gain by rounding off plugs only poorer performance, the proof is in the scope pattern. Anyone out there with a scope can verify this and post reply. Regards Jack McIntyre.

I'm not talking about touching the electrodes,(assuming that's the copper bit in the center of the plug base), I'm talking about the part that comes up that the shock from the copper shoots to. Rounding that off, instead of having it square... Blah blah. I hope everyone knows what I'm talking about, it's kind of hard to explain I guess without a picture. Or maybe I'm wrong thinking that the copper part is the electrode?
--
Kyle - '68 142? - Oregon Volvo Tuners?

Why not use a set of Bosch Super 4's which have 4 electrodes of varying lengths - these would save the bother of trying to achieve this.
Not cheap but are said to have a use life of 60k kms.
TimC

Super 4s? Are those different from the Platinum 4s? I've never heard of super 4s... But in either case, that sounds wierd, and I don't see how it would accomplish the smaller area for the spark to go to. Which I think is what the benefit is here...
--
Kyle - '68 142? - Oregon Volvo Tuners?

If radiusing the ground electrode was a good idea, NGK would do it. It isn't a bad idea, but it won't contribute to anything.
Idexing the spark plugs has been discussed for years, and no one is really capable of saying whether the gap should face the intake valve, the squish zone, the piston, the whatever. The jury is still out on that one too.
Extended tip plugs, wide heat range plugs, are all good developments. Multiple electrode plugs have been used for years in aircraft engines, and for some reason many think they are a good idea in cars. They probably aren't.
Check out www.ngksparkplugs.com and read up, or find a copy of the Bosch Engine Electrical text, which may very well be one of the best books on the subject.

Hi there -

I read the article in Grassroots you're referring to (lastest issue). The impression I got is that you'll have to file them yourself.

Along the same line, I have a tech tip for you. pay attention to where the gap is facing as you screw in the plug, You want the gap facing towards the center of the chamber rather than the wall near the plug hole (follow me?) That way the flame will be facing the whole of the chamber as opposed to the spark plug having "its back" to the chamber.

You may have to use shims to position the plug the way you want it.

My race head came to me with the polugs indexed like that. They had marks on them indicating the electrode direction, and two of them were shimmed to snug into the proper orientation.
--
I'm JohnMc, and I approved this message.