After comparing the same models hashing LTC vs hashing BTC I got a average number of about 996kh/s per 1 GH/s.
So yes roughly 1/1000 ratio between LTC vs BTC in hashing.
That ratio is only pertaining to GPU's right? Reason I ask is that when I use bitminter I get 60khs for BTC but I get 2khs in LTC
Thats with a CPU