I Have 380 Cc Silicone Implants Would It Be Possible to Change to 800 Cc?

Anything is possible BUT 800cc implants are way too big for your frame and those implants will have serious negative effects on your breasts over time.

It is in your best interest to be examined by a board-certified plastic surgeon experienced with the use of larger breast implants.  I like to communicate with my patients  with the help of pictures of what the patient's goals are. You may be able to achieve your goals with implants smaller than 800 mL.

Of course, it is important to consider the downsides of larger breast implants and larger breasts as you are considering your options.