On my GeForce GTX 660 Ti, I used to get around 245 or so and now I'm pushing around 270.
My config is cudaminer.exe -H 1 -m 1 -i 0 -l K7x32
I tried H2 but it shaved off about 10 k/h

I also tried C 1 and though it added about 9 kh it felt like it was pushing the card too hard.  I can already hear the fans spinning up where before they were inaudible which makes sense but might be something I'll have to ease into and get more detailed temp reading about.

Thanks much bud, you're doing great work.