PapaV here..............I see all and read all about D3 and their spark plug upgrade or their D3 Torquemaster Plugs (one in the same??) and I'm wondering if the current NGK's that the previous owner installed in 3/2010 are compromising the performance of my STS-V's Stage II Pkg?

The NGK's he had installed when the car had 29K miles on the clock occured when he had it retuned in Michigan f/ 93 octane (as opposed to CA 91 max).

The car now has 43K.

If and when I replace the plugs what should I install?

My mechanic said that the GM spec original's would probably be best.

And while I'm at it.....what does D3 recommend for oil w/ their Performance packages??

What Say You?