Place potatoes in a large pot and cover with cold water by 1 inch. Add vinegar and 2 tablespoons salt.
Bring to a boil over high heat and cook until potatoes are just cooked through, about 5 minutes after coming to a boil. Drain potatoes and let rest over sink until mostly dry.
Heat 4 tablespoons vegetable oil in a large non-stick or cast iron skillet over medium-high heat until lightly smoking. Add potatoes, shake to distribute around the pan, and cook, tossing and stirring occasionally until very crisp and golden brown on all sides, about 15 minutes.
Meanwhile, heat remaining oil in a medium non-stick or cast iron skillet over high heat until shimmering. Add chorizo and cook, stirring, until heated through. Continue cooking, stirring and tossing frequently, until all the liquid has evaporated, some fat breaks out, the chorizo starts sizzling, and eventually is quite dry and well-browned, about 15 minutes.
Transfer cooked chorizo to pan with potatoes. Toss to combine and season to taste with salt. Serve chorizo and potato mixture immediately with tortillas, onions, cilantro, salsa, and limes on the side.