Well, I guess that varies program to program. Some might take an average and create a cutoff for the average, but the problem is that most people don't have a step 2 in by the time the apps are initially reviewed, so some programs might just use step 1 as a cutoff point. Thats where you would run into problems, even if u do do very well on step 2.
If they have an actual person look at each app and look at both scores before giving interviews they will probably look more at your step 2 score, since it i thought to be much better indicator of clinical ability. Whether any programs do this, i don't know.
Once you get an interview at a program though, if you have a good step 2 score, most people will disregard the step 1 score as a fluke. But your step 1 score will pose a problem getting interviews even if u do well at step 2, especially at cali programs that have a large # of apps and probably don't look at each too closely. (This is not to say you shouldn't take step 2, I still think it is important for you to take step 2, otherwise you will have a hard time getting a decent program anywhere)
To help score interviews in cali I would sugest away electives at these programs, that will proabbly land you courtesy interviews at the least, and then your step 2 could enter the pictures. Don't go for away's at the top cali programs like stanford or ucla, shoot for more realistic programs in cali, unless you are certain you can ace the step 2 with a 230+.