Increasing your speed on the ACT really comes down to practice. The more you practice, the faster you will become, hopefully. When I do practice tests, I read the ACT Reading passages in about three minutes and then do the questions. If you read the whole passage and digest it, the questions will become easier and you will be able to work through them faster. For science, I usually skim the passages and the graphs/charts/etc. so that I get an understanding of the experiments and then I answer the questions.
I found these guides to be very helpful:
ACT Tips to Succeed
Jeandevaches' Guide to the ACT
I have heard that Barron's 6 ACT Practice Tests is a very good practice book, but I have heard that Barron's ACT is not that good of a book. You already have many of the practice books that will help you in preparing, but if you run out of practice tests than buy Barron's 6 ACT Practice Tests. I don't know if the tests are harder, but they will still help you prepare. Make sure you go through Barron's ACT 36 because the book is designed to challenge people who want to score high.
Also, if you need additional practice tests, here are some links to official ACT practice tests that I found on the forum:
http://www.sdcoe.net/lret/avid/act/PreparingforACT.pdf http://www.collegetidbits.com/tools/...or-the-act.pdf http://www.unioto.k12.oh.us/ACTpreparing.pdf http://www.ashland.kctcs.edu/Admissi...tice_Test.ashx http://www.act.org/aap/pdf/preparing.pdf
Good luck in preparing for the ACT and I hope you reach a 35/36!
