I use a Nema 23, 4.2 amp on my BOXFORD lathe and although I have stalled it, I was probably asking too much of it and it is almost a safety feature. I would have thought that there is plenty of power in that setup for your lathe. If in the future you wanted an Electronic Leadscrew, you would be half way there. I installed an ELS and have never looked back – its a game changer as far as I am concerned.
The Boxford has a combined leadscrew/feedscrew . For turning, I prefer the feed option so that the half nut wear is reduced. This also allows for power cross feed.
Bob