Originally Posted By: bunnspecial
I'm running NGK BPR6ES plugs, which are the resistor version of what a lot of folks on the MG experience swear by. They're a copper plug, but I like the big center electrode that supposedly is less resistant to fouling than the small electrode on platinum plugs.
In any case, I'm running a .025 gap in them(or at least that's where I set it when I installed them 3 weeks ago). The ones I took out were about about .030, and I've been wondering if I should open the new ones up to that. I have to admit that I've been worried about stressing the oil coil too much, but it's a cheap enough part that I'd sacrifice a shorter life on it for better performance and especially easier starting.
I'm definitely going to put the old wires back in, though, and go shopping for a better set. Of course, I suppose the problem could be in the cap or rotor, but I really think it's the wires.
I have to admit COP ignition is nice. When I did plugs in my DD about a year and a half ago, I bought the OEM NGK Platinum-Iridiums and used the out of the box gap(.045). Amazingly enough, the 125,000 mile factory plugs retain that gap. I think you need about 40KV to jump a .45 gap, which a COP system can handle without breaking a sweat.
In my old 1971 Volvo 142E
I converted the points to electronic ignition with the CRANE XR3000
I hung a 45k crane coil on the fire wall to go with it.
with the bosh D-jetronic (electronic fuel injection) and the electronic ignition it was pretty much like starting a modern vehicle. I ran NGK plugs BPR6HS and opened up the gap to about 0.035". The big flame from the large coil and the bigger spark plug gap made it run very well. I would every so often check the timing but it never changed. I went with the xr3000 over the xr700 because you could use a larger coil
If I had an old car with points I would drop them like a bad habit it will make tuning much easier.