My experience with the LSAT is that the first 30 hours or so of study are going to give you a significant boost. Your next score bump comes after about 150 hours of study.
The writers of the LSAT have stated that a person needs to study for 6 months to do well.
The good news is that you have plenty of time left. The LSAT is so important that I would recommend that you take a live prep class. I know it is a lot of money. But, isn't getting into a tier 1 school worth that money? I think the 160's are within reach for you, whether or not you take the live class. The live classes tend to avg. +3-5 points. I think it's because you will get an experienced coach who can watch what you are doing and help you to tweak it.
Regardless, take a bunch more practice tests. Good luck, and let us know what happens!
Obviously the OP needs to put in additional quality
prep/study time to further improve his/her score, that is a given.
However, I take issue with your generalizations and the supposed statistics you claim to be true (especially the above bolded parts).
If you have reference sources that support your claims and stats I'd love to see where you got your info from, since I'm pretty sure none exist. To my knowledge LSAC has never taken a position about how long it takes to adequately prepare for the test or made any specific 'how to' or 'how long' LSAT prep recommendations aside from the study guides and test question explanations included in their SuperPrep book.
How did you come up with the idea that live prep class students average 3-5 points improvement? From my many years experience teaching classes and tutoring students I think your figure is low. However, since outside of the internal stats prep companies keep about their students (which they don't make available to the public) there is no available large empirical data source of students first practice test score + final reported score, which makes your claimed statistic merely a guess.
Please don't guess/make up generalizations or numbers and try to pass them off as facts/statistics to students.
There is no "One size fits all" formula to successfully prepare for the LSAT and significantly improve ones score. Skilled experienced LSAT teachers/tutors generally do not/will not make claims along the lines of: X # of hours per day/week of study/prep, Y # of weeks/months of prep, or taking X# of timed practice tests should or will or are needed to achieve Z # of points improvement or whatever scaled score, since no such formula/metric exists.
To the OP John1990:
You have plenty of time ahead of you before the June 2011 LSAT, so you should not be worrying about timing (finishing sections in 35 minutes) and taking timed practice tests now. Instead you should spend your study time working and analyzing the questions in slow motion, reviewing the concepts and applicable strategies and techniques, reviewing the concepts, questions you missed, mistakes you made, areas/concepts/question types that are giving you more trouble than others, etc.
Simply doing the "churn and burn" routine of taking a bunch of timed sections/full tests does not do much to improve your understanding of the concepts tested and your resulting analytical/reasoning skills that you need to apply to the questions in order to answer more of them correctly. You should spend a good portion of your study time reviewing everything and balance that in with practice/working problems time.
Focus more on accuracy and understanding right now instead of simply trying to work on your timing. Timing improves naturally with better understanding of how to analyze and go about approaching each question/section type (meaning improved skills = improved accuracy and less time needed to solve each question correctly).
One thing you might want to try that would be a good way to help you identify weak areas/concepts/etc. you need to work on/review/improve is to take a a full test you haven't seen before untimed in one sitting with the goal of getting as many questions as you can correct (try to get a 180 untimed without cheating and also without time pressure).
Just you and a fresh preptest for a day. Work through each section without ever checking the answer key or looking at other prep materials until you have selected what you believe to be the credited answer choice for each question. Doesn't matter if you spend up to an hour or more per section and take some breaks as long as you do it all in one sitting/day without looking at/using anything else to help do it other than your pencils, eraser and maybe scratch paper. When you are done and have made a firm decision for every question, then score it. You will probably be surprised at the result since most people incorrectly believe that they or anybody else can/will get a 180 when not faced with the time pressure.
The questions you answer incorrectly when you do this will highlight your current reasoning errors, concept mis-understandings/weaknesses and lots more stuff that is helpful to know in order to guide further directed study aimed at shoring up your weak areas/vulnerabilities.