I've got very large (1150cc) breast implants. Will I be able to start Crossfit? What about weight loss (30+ pounds)?

The major concern would be the length of time since your breast augmentation.  I would definitely advise you to wait three to four months following your surgery before beginning extremely strenuous activity.

Thank you for your question.  Congratulations on taking an active role in your ongoing health.  Unfortunately, a significant weight loss is likely to have some impact on the appearance of your breasts especially since your implants are very large.  They may also impact your ability to do some exercises comfortably.  Having said that, it is still a good idea to get to your ideal weight.  You will have to address the limitations and consequences of having large implants as they arise.  Best wishes.

I am going to change the question a little.  where did you get the1150 cc implants. I would have some larger reconstruction  patients for whom they would be useful?

I think that besides talking to your surgeon, you should talk to a medical doctor to make sure it is safe for you to start such vigorous workouts.

Your plastic surgeon, will always be your best resource. Generally speaking, in the long-term, patients who have had  breast  augmentation surgery (even with larger implant/volumes) do well returning to strenuous exercise. Also, generally speaking, best to “go slow" and listen to your body as you begin the intense workouts. Unfortunately, it is not possible to predict with any degree of certainty exactly how your breasts may change with 30 pound weight loss. Hopefully, with the gradual weight loss, based on good diet and exercise, the changes will be modest. You may find the attached link, dedicated to patients who have  have breast augmentation with larger breast implants, helpful to you. Best wishes.

You should be able to return to full activity but you need to be more conservative and wear supportive bras's and if anything changes, contact your plastic surgeon.