In 3 months you could get up to 250 hours if you worked hard at it. I got about 100 hrs last year in florida in 4 weeks with about 5 hrs a day or so. Have a look at Debenair in titusville. They're great and very friendly. They are also starting to do JARs now. I'm going back to do my CPL IR. Doing my ATPLs DL with Bristol Ground School. I would highly recommend them, their notes and feedback is brilliant. If your going USA for 3 months, get a multi CPL or PPL and get as many multi hours as you can cos thats what counts now. Just make sure you got your class 1 medical first.
Good luck