How many lights would you put in this room?

I am starting another flower room. It is 11' x 8.5' and 8ft ceilings.

HOw many 1000w hps would give enough coverage, planning on vegging for 8 weeks and having 12 "tree's" in it, hanging the bulbs vertically.

I was thinking of going with 6 x 1000w, but worried it might be too small of a room for it. Any opinions?

6 would be a lot. Ideal space for a 1000 watt is 4x4. In my experience when the bulbs are much closer than 4 feet from each other you get hot spots where the overlap is. You could either do 4k and have an 8x8 foot square,or possibly get more lights in there if you run them around the perimeter of the room against the wall..like a horseshoe, with a break in the canopy for the door. You should get some graphing paper or something and cut squares that represent the 4x4 for each light and checkout different configurations.

Edit: Just noticed you said hanging the bulbs vertically, not experienced doing that but maybe you can fit more that way since the light isnt concentrated as directly as with a hood.

I have same size room an 6 lights 2 x 1000 an 4 x600 watts. But as other poster says I use cooled hoods and mini split AC to cool down as gets very hot in there.