DVD+R DL: force overburn even further

My DVD+R DL stopped burning at 8.53 GiB (around 8.01GB?) due to 05 21 00 LOGL BCK AR*SS O OF R**GE. (I hate this error that much).

How can reading and burning be enforced to go beyond these ugly limitations? Optiarc hit 8.7GB on DVD+R DL, so enforcing the burn should also enable that on the BU20 I was using. (×2.4 CAV burning speed because it is a laptop drive,to maintain quality).