My boy Bullet does the same thing. I tried everything I could and couldn't get him to slow down, so I got one of those Brake Fast bowls, and it works wonders! He still tries to eat as fast as he can, but the posts in the middle of the bowl make it so he can't get enough in his mouth at one time to choke himself. Here's a link to the site where you can learn about or buy them.
Welcome to brake-fast.net! Since your dog is still a puppy, I would definitely go with the small size, and meduim is good for full-grown pits (that's the one that I have). I bought mine off of Amazon and got a much better price on it, so you can probably shop around if you're interested in getting one. I'll give you a few other suggestions too, if those don't work, I would go with the bowl. Anything you try could take at least a few weeks of consistency before it sinks in. Whatever you do, make sure to stick with it for a while before you decide to try something else. Trying different things too quickly can often make the problem worse. I would give anything you try at least 2-3 weeks before moving on to a different tactic if the first one doesn't make a difference. If at any time you see even the slightest bit of improvement, keep doing what you're doing and she will continue to improve.
Does she know the sit/stay command yet? If so, make her sit and stay and wait until she is nice and calm before you give her the food, that way she won't get as excited and that might help with her eating so fast. Since you are the "pack leader/master", she should be eating on your terms so that she will view you as the dominant leader. Don't let her have it until you give her an OK command, and that might fix the problem.
Do you have any other dogs in the house? If so, she could feel like she has to compete and that could be why. Try feeding her in a separate room where she can't see the other dogs and that might help if that is the case.
Do you know if the person you got her from fed the litter of puppies all together from one big bowl or did they feed them individually? Very few breeders will do that, I've found, but if they fed them all together that could be another reason why, she's still thinking she has to compete for her food. If there aren't any other dogs in the house, I would just give it some time and maybe split up feedings and feed her a few more times in a day if possible. That way she won't be so hungry by the time the next feeding comes. The first puppy I got was the only dog in the house at the time, and did the same thing that your dog is doing because the puppies had been fed all together from one big bowl. It took her a little while to realize that she didn't have any competition anymore, and I was eventually able to free-feed her.
I've had a few people tell me that letting them eat as much as they want helps too, that way they realize that their food isn't going to go anywhere and they chill out about it within a few days. That didn't work at all with my guy..... he just kept eating until he looked like he swallowed a basketball, and then it all came back up a few minutes later. I've heard that it does work for some dogs though.
Sorry, kinda wrote you a novel, but those are my experiences. Hope I was able to help!