the 512 in my 72 Challenger is still pinging on me. The motor is a 512 stealth aluminum heads Holley 950 HP carb Comp cams XE295HL-10 cam, 11.3:1 compression, MSD 6Al, MSd Billet distributer, 3,200 Rpm Stall,2"TTI headers, 3" pipe to 3" Flowmaster 40 series , 3:55 gears. Timing is 16 initial 32 total all in by 2,800 RPM. The pinging occurs at about half throttle and it's a pretty loud ping The things I have done to try to solve the problem are

1. Brought the timing down from 34 total to 32 total
2. Upped the primary jets 4 sizes
3. increased the power valve from 2.5 to 3.5
4. Added 5 gallons E85 ( 110 Octane )to 10 gallons of 91 octane
5. went up 2 heat ranges on my plugs


Nothing helped at all I'm at a loss on this problem. Could it be that I'm bringing my timing in too soon? if all of my timing is in at 2,800 and my stall is 3,200 could I be too far advanced when the stall comes in? My engine temps are 185-190 and pretty steady, At this point I'm willing to try anything. I prefer not to tear the motor down but at this point if I need to I will before the pinging tears the motor apart for me.