Faster and/or more hard drives would be my idea... but, since you don't provide any hard drive information, that is only a guess
>once loaded my system is extremely slow
Only 8Gig of ram is very light for such a large project
If I may be so bold as to offer workflow advice? When working with an underpowered computer, there are ways to work around the RAM issues and the slow processor.
Break up the project into various sections. Work on the intro and the credits in one project, work on indoor scenes in another, outdoor in another, or some other manner that allows you to use multiple projects. When you are done with a section, or a scene, or whatever, you can nest the main sequence and import that new sequence into the "main" project where you can then assemble all of the parts.
If you really need to go back and make adjustments, just reopen the original project for that sequence and do what you need to do. Then delete the sequence in the "main" project and import it again. Or, instead of doing that, just export each project's main sequence and combine the clips into one new project. You would not use this method for the final export, but it will save you the hassle of importing sequences over and over if you are changing things a lot. When it all looks good, then import all of the projects into one project and combine the sequences into your movie.
Keep in mind that a Premiere Pro project is just an XML file and all of the text has to be read into the program, basically one line at a time. So keep the number of lines to a minimum. Even in CC, it is still XML, just zipped up.