Best Way to Back Up a Blu Ray Disc Main Movie Only under 4GB file size for use w/PS3 fat32 ex hd?

Hi Guys-

I'm new here and I have searched and searched.. There are many of Torrent Sites that have Blu Ray Rips under 4GB total file size, typically like 3.99 for the Main Movie Only. I have a PS3 connected to a External HD Fat32 and need the total file to be under 4GBs. I already have the ACVHD program to switch back and forth for the movies that I want to be big file sizes, but for the only that are "mediocre" I want to back these Blu Ray main movies up under 4gb file size..

I first need to know how to take off the DTS audio and switch it to the AC3 5.1, then obviously make the file size of the blu ray main movie to 4gb. Please help me guys! and here is an example of the what the PS3 team is doing on the torrents :


Specifications

* Codec -----------> H.264
* Resolution -----> 1920x1080
* Average Bitrate -----------> 3.6
* Framerate ------> 24fps
* Audio ------------> AC3 Dolby Digital 5.1CH Surround (384Kb)
* Subtitles --------> english subs for african dialogue
* Extension -------> M2TS
* Source-----------> Blu Ray Disc
* Movie Trvia------> Leonardo DiCaprio and Russell Crowe were Edward Zwick's first two choices for the role of Danny Archer.
Procedure And Testing
* This file is kept under 4 gigs for easy storage (Dang FAT32!) Hi quality 2-pass H.264 standard encoding.
* THIS IS MEANT FOR PLAYBACK ON THE PS3 and was Tested on Sony Playstation 3 (Firmware 3.00) with a large 52” screen (LCD
) HDTV .

 

I am assuming I'm going to have to use RipBot264 for the video and set it on 2 Pass .. and change the file size to something under 4gb.. but how do I go about changing the audio from the DTS to AC3 and maintain the 1920x1080 resolution in Ripbot264? Please help me guys.

 

i just had to use this myself, follow this guide

http://www.afterdawn.com/guides/archive/convert_dts_to_ac3.cfm

 

I have two threads right here...

http://forums.afterdawn.com/thread_view.cfm/639346

http://forums.afterdawn.com/thread_view.cfm/621809

However, I wouldn't recommend a 1080p encode targeted for the 4GB mark. Even if the uploader claims that it was tested on a 52" LCD. There is definitely a noticable decline in quality with that level of compression. I use higher level settings (available for download from the links I provided) than almost all found uploaded via torrents and I still can not retain 1080p with a high level of quality with a bitrate as low as 3600kbs (as the torrent has listed). My absolute lower limit for 1080p is 6000kbs and even that is borderline.

My rule of thumb is 4.35GB=720p (DVD5) and 7.95GB=1080p (DVD9).