In case someone else stumbles here... you can set padding as well, for instance:
Toolbar toolbar = (Toolbar) findViewById(R.id.toolbar);
int padding = 200 // padding left and right
toolbar.setPadding(padding, toolbar.getPaddingTop(), padding, toolbar.getPaddingBottom());
Or contentInset:
toolbar.setContentInsetsAbsolute(toolbar.getContentInsetLeft(), 200);