I would advise caution here. I've never adjusted the torsion bar (also called a truss rod) on my acoustics but have done many truss rod adjustments on electric guitars and electric basses. Always loosen the strings first and only do a 1/4 turn at a time. If you inadvertently hit the end of the truss rod travel and try to go past it, damage can result. So small adjustments, retune the strings, wait a bit and see if the neck flattens enough. Sighting down the neck you can see what is called "neck relief', or a slight bow in the neck, a little is normal. Many manufacturers have specs for each model specifying the normal relief, there is usually just a bit.
Measuring the "relief" first before adjustment is a good idea. I use a spark plug gapper.. The explanation is too long. Here's some info.
There are other ways to lower the action, such as lowering the saddle, but amateur luthiers should leave this to a pro unless you have a beater guitar you want to experiment with-I've done this. Don't do this with your Gibson or nice Martin!
Even truss rod adjustments, a suggestion would be to have a luthier do this for you once and see how it's done properly, before messing with an expensive guitar.