11X multipler would give much more room to toy around with, although I would recon your most likely drop the multipler and raise the FSB, as it unlikely with air cooling you will achieve 300 x 11 =3.3GHz, it more likely you get something like 9 x 300 =2.7GHz. Saying that the 175 would have been binned to a higher level, meaning its more likely to overclock better, plus the fact if your unlucky and have a motherboard that wont allow much on the FSB front you still have the higher multiplier so it possible to get a higher speed.
Its also worth noting that good RAM and good air cooling will play a major part in this overclock.