Here is my second version of the sauce. Excellent IMO.
1 cup ketchup
1/3 cup cider vinegar
1/2 cup brown sugar, heaping and packed
1 Tbls Worcestershire sauce
1 Tbls Rib Rub
1/2 tsp fresh ground black pepper
1/4 tsp liquid smoke
Add ingredients to sauce pot and simmer on low for 30 minutes.