I make some changes over the post before storing it in the database.
I use content_save_pre to do this.
Some characters like " get done into “ in the JavaSript code which I insert (part of the change). How do I prevent that from happening?
It seems that the "convert_chars" filter is causing the trouble, try removing it by:
remove_filter( 'the_content', 'convert_chars' );
Also try removing the richedit_pre hook (which formats the text for the rich text editor, also uses convert_chars function) by:
remove_filter( 'the_editor_content', 'wp_richedit_pre' );
Hope that helps!
wptexturize()is doing this on the fly at runtime, so knowing the structure is important for figuring out how to stop it.