Only a few drive models will overburn DVD+R media, and no currently manufactured DVD burners will do so.
I’m can’t think of any DVD burner that will overburn DVD-R media.
If you have one of these drives, you can overburn DVD+R media:
BenQ DW1655, DW1650, DW1640
Plextor PX-760, PX-755, PX-716, PX712
There might be one or two more BenQ and Plextor drives that I missed, which also support overburning DVD+R.
If you have one of those drives, you can overburn in ImgBurn without having to do anything special in the software except confirm you want to overburn.
For the BenQ drives you will have to disable SolidBurn for the type of media you want to burn (known or unknown) since SOlidBurn will interfere with the overburning. You will also need to overburn by a significant amount, since small overburns of just a few MB don’t work IIRC.
Have a look in the BenQ DW1655/DW1650 overburning thread
If you don’t have one of these drives, you cannot overburn DVD+R media.
Your Sony DRU-810A is the same hardware as a BenQ DW1640, so it may or may not support overburning with Sony firmware. If overburning doesn’t work with Sony firmware, you may consider cross-flashing your drive with BenQ firmware. There should be a description on how to do this somewhere in the BenQ forum.
EDIT: There’s also a Sony DRU-810A[B]-R[/B] which is the same hardware as BenQ DW1650, and you don’t want to use the wrong firmware in a cross-flash, or you may kill the drive.