Engine pinging? what to do??

A longer duration on the intake side with a later closeing intake valve might bleed off enough compression to run without pinging. The overlap happens at the end of exhaust/begining of intake cycle and actually raises the compression at some point in the RPM range.
I run 10.5-10.65 to 1 on 93 at sea level +600 with iron heads but have .037 quench area and its drag race only. It may be detonating,who can hear it with open headers? Its holding together so far.
Has anyone tried running E85 fuel mixed with premium? Ethanol burns cooler,has a 110 octane rateing,and should be cheaper than race fuel and leagal to run. You would need to increase fuel flow by 20% or so because ethanol contains O2 so mileage would be poorer.
And Brett you can buy E85 in WBurlington. I havent tried this myself but am trying to research it. Claims of 5 to 10% more HP are the rumor. A methanol carb might work if jetted down. Just rambling.