How is your carb set up if you don't mind me asking? The 360 in my Duster sounds fairly close to yours, but with the 600 Eddy AFB I have, it has a nasty ping when it gets up in the revs. I have a 650 Holley double pumper that turns the car into an powerhouse, though the AFB is much easier to drive.
As far as I know nothing has been done to it. The 360 had a Thermoquad that the previous could not get to act right. He had pulled the 600 off of his Montecarlo. It's been on there ever since.
What octane gas are you using? If I use anything less than 93 it will ping like a mother.
A friend of mine has a 650 DP that we were going to try on my car but we didn't have the bracket for the TV cable going to the trans.
