This hack offers six different options for adjusting the pace of spell grinding:
~149%, or about 1.5x as much grinding (~270 casts per elemental). (Has serious side effects, see below!)
~77%, or about 3/4 as much grinding (~141 casts per elemental).
~64%, or about 2/3 as much grinding (~117 casts per elemental).
~55%, or a bit more than half as much grinding (~100 casts per elemental).
~48%, or a bit less than half as much grinding (~87 casts per elemental).
~32%, or about 1/3 as much grinding (~58 casts per elemental).
Important things to note:
The original game is roughly 181 casts per elemental.
All figures listed here are for combat zones. When in a non-combat zone, grinding takes twice as many casts.
The 149% hack has a couple side effects: 1. You cannot gain spell levels past level 7 in non-combat zones and 2. You cannot ever attain the 8:99 special spells under any circumstances.