1. In medium-size saucepan, combine 2 cups of the water, sugar, salt and chili powder. Bring just to boiling, stirring to dissolve sugar and salt. Add remaining water; let cool.
2. In large bowl, combine pork chops and chili powder mixture. Refrigerate 6 hours or overnight.Grilled Salsa:
3. Heat grill. Grill tomatoes, onion and chiles until charred, 15 to 20 minutes, turning every 5 minutes. In food processor, pulse chiles and onion until finely chopped. Transfer to bowl. Core tomatoes. Pulse in processor until coarsely chopped. Add to chiles along with cilantro, vinegar and salt. Refrigerate until serving time.
4. Drain pork chops; pat dry. Discard marinade. Grill until instant-read thermometer registers 160 degrees F, 12 to 14 minutes per side.