Thank you gentlemen for your thoughts – they are greatly appreciated.


I suppose what was of concern to me was any possible impact that the very different finishes (Ni vs. ??) between the newer and the older BP5ES plugs might have on conductivity, temp, etc. and would it really be enough of a difference to matter.


Given that they are not the easiest plugs to come by around here - combined with my frugal streak - I think I'll mix them - alternating by firing order - and see how that works out for me when I do my tune-up this weekend.


I agree that they should be 100% compatible/functionally identical (famous last words) in theory but am now curious to see how it all plays out in practice.


Cheers!