Does anyone have any motor suggestions for catalyst machine works 7inch Merica build? I was going to go with 2808 1500 kv but I'm getting a lot of different suggests and unsure.

Depends what you want from the quad, style of flying, potential range...............etc..........

And especially the expected weight depending on type and capacity of batteries used, 2808 1500 kv will easily handle weights above 1,5 kg and more ... for lighter load you can use something smaller like 2806.5 to save some weight. If it should be for chasing I suggest higher kv for 6s, with 1500 kv it will not easily go over 130 or 140 km/h with common props.