What suspension upgrades should i do for $1200 big block dart

Yeah, I like the way it sits and how it rides. I haven't had a problem with them yet. I got mine from Summit back in late 2014, early 2015. A lot of people claim they're too low, but I like them. If you're running 15" wheels with a tall tire you may have problems with rubbing when the tire flexes. My sidewall is pretty short so I don't have that problem. I may go to composite leafs in the future, but we'll see.

@72bluNblu, don't you have some AFCO springs from summit and don't they come in two different stiffnesses? The less stiff one may be better for the OP.

For $1200, I'd probably do MOOG offset bushing, welded in subframe connectors, Bilstein RCD shocks, and Hellwig sway bars front and rear. As mentioned before, your tires are your limiting factor.
can you tell me what sizes for the hellwig sway bars ?