Thanks, Arne... would they be suitable with a Pertronix with stock coil & ballast (still connected as per Pertronix instruction sheet)? I have read debate on this forum about having the resistor connected, but I followed the instructions. Didn't upgrade the coil, either. Any opinion on that with the -11 plugs?

I wouldn't think that the stock coil with ballast would have any hotter spark than the points, just a whole lot more accurately fired with the Pertronix. So I think I'd stay with the smaller gap in that case.

NGK here as well. Use the -11 for electronic ignition. If you're using points, stick with the normal BP6ES.

What is the difference between the BP6ES and the BP6ES 11 plugs?

I have the MSD 6A, Mallory Unilte and the Promaster coil. But I use the regular BP6ES. what would changing to the 11's do for me and why.

Dave.

EDIT. Never mind. DUH. just read it.

I'm running NGKs as well. If you can't find them, keep shopping until you find an auto parts store that carries them, and don't buy anywhere else! Make sure your money goes to the places that put forth the effort to carry quality parts.

A comment was made above about the BP6ES-11 or BPR6ES-11 being for the EFI cars. That would be B6ES-11 or BR6ES-11. No 'P' on the EFI cars which stands for projected tip. A projected style spark plug increases the firing tip temperature by 10°C to 20°C. I guess that isn't necessary on EFI cars but you carb guys should consider that when swicthing to electronic ignition. And it doesn't matter if you use the -11 or not since you're probably going to check/set the gap yourself anyway. I always do.

Numbering explanation for NGK Spark Plugs

And it doesn't matter if you use the -11 or not since you're probably going to check/set the gap yourself anyway. I always do.

True, I always double-check the gap before installing them. But I like starting with a pre-gapped plug close to what I want, that way no big adjustments are needed, just small tweaks. So for stock coils with ballasts I use NGKs without any suffix (pre-gapped at .9 mm or .036"). For hotter coils I use the -11 (1.1 mm or .044").

NGK

Haynes manual even recommends NGK. The cheaper ones too.

There are new lazer beem ones that I would like to try, but I am sure they they would do some serious damage.

I use ngk, they're a japanese company originally so that kinda adds to the whole nostalgia of the car too. Talkeetna, thats my new favorite place (only because of west rib and their ice axe ale, good stuff!) I'm originally from anchorage. Nice to see Z's alive up there!

(the musk ox burger with fat arse sauce is amazing as well!)

girlfriend with my z -doesn't get much betterQUOTE]

Awww, I was getting excited. I love hot girls with Z's. Great looking car!!!!

Japanese car... Japanese plugs

I installed NGK Iridiums, a bit pricey but seem to fire hotter and definatley last longer

hey, whats the difference between bp6es and bpr6es? pepboys gave me bpr6es......