Just noticed that the wiki says it outputs half as much as it actually does. No idea how i did that, but the turbine gives out 80L steam per 1L lava. Not 40L. Just to declare it not OP, the HP Lava Boiler produces 100L Steam per 1L lava and i lowered it from 150L. No one cared about that one even before i lowered it.
It's not OP in my eyes because it isn't the stopgap quick n dirty solution it used to be. You practically need an engineering degree to have a proper setup and even then you'll eat lava so fast you'll have to replace a nether pump daily.
On a related note: now that I know how much steam that makes I'll probably throttle lava consumption to 250 L/s and use a configuration 5 IC, take the 7.5% hit in efficiency, and use 20000 L/s turbines (there seem to be a lot of those and plumbing is easier with only one pair of turbines.