Hey Stevil, When fueling up my 1985 32 valver it would ping a bit on Regular fuel if I accelerated too rapidly or stomp down on a steep grade to pass. I think part of my problem is that the compression is a little higher than normal from a slight build up of carbon on the bottom of each head. The good part was that when I scoped the cylinders during the initial retro-furbish, I was lucky to find no cylinder wall scoring.
One of the many threats generated during a cylinder ping is that the harmonics can dislodge a small particle of this built-up hardened carbon. If it lodges between the piston and cylinder wall, it could score a vertical line along the piston ring sealing surface. Eventually this can cause oil consumption, blow-by and ultimately a loss of compression. So the main reason that I use Premium fuel in the 85 is to try and avoid the ping.
My 84 16 valver seems to digest Regular with no problem, even when pushed hard.
Good Luck, Michael
