The 'holy grail' is 1 gram/watt, so 2.2 pounds if absolutely everything goes perfectly. Of course, there's a lot more to it than just your lighting, but that's probably the single biggest factor affecting yield. Not many achieve that though, and certainly not in their first few grows. Realistically, hope for half of that and if you get it, be happy, and consider anything beyond that a bonus; it's better to be a pessimist and pleasantly surprised than an optimist and completely disappointed.

That's a pretty small space for a 1k light, btw, and really more suitable for a 400w light. Hope you have all your ventilation needs figured out and taken care of!