Stock Compression on that motor will allow you to run regular, those heads ar eopen chamber, so increasing compression will make it much more likely to ping. On the opposite side of that, pistons not being flat with the deck are more likely to cause pinging then if they had been put at 0, even though the compression goes up. Dont ask me how, But Its what I've always been told.

So ya think that 268h is a lil small? I've got one in my 460 and it has no torque curve, darn near flat all the way across. Does drop off about 4800, but hey, its a truck engine. Only real bad part of this much torque is I cant get traction till around 55 when I hit 3rd. Im runnin a 33 x12'' tire, and they spin like a cobra runnin Donuts at the track. Actually wish they hook better, they spin all the time, and not only am I attracting the attn of cops, Im also goin through $130 tires like crazy. Maybe a welded diff.......
[addsig]