WR6DC+ spark plugs

I prefer copper plugs over any other kind out there, esp Bosch ones. So yeah it's a good plug to me.

There's been threads in the past on best material for plugs, my stance coming from physics is copper sits at the top in terms of 'best'. The only downside to copper is that it doesn't last as long as the other ones, but it also does not sacrifice spark energy for life cycle.

 

On my 82 GTSi I use 500 ohm/ft wire, zero ohm extenders, BP7ES plugs (non res)

 

For a '85 308 QV which is injected I use NGK BPR 7 EIX gapped at 0.028

 

The Iridium Plugs have a finer tip and use less current as well.

 

I have always been confused about tip. Thick or thin? Grooved. What are pluses and minuses?