Step 1: If your butcher hasn’t yet done it, trim any silver skin or excess fat off the pork roast. Place the roast on a sheet pan.
Step 2: Make the rub: Place the coffee, sugar, paprika, salt, pepper, and cumin in a small bowl and mix with your fingers. Sprinkle the rub over the pork on all sides, rubbing it into the meat. You can cook it right away, but the roast will have even more flavor if you let it cure in the refrigerator for 2 to 4 hours.
Step 3: Set up your grill for spit-roasting and preheat to medium-high (375 to 400 degrees).
Step 4: Thread the pork roast lengthwise onto the rotisserie spit. Place on the rotisserie. Toss the wood chips on the coals or place in your gas grill’s smoker box. Spit-roast the pork until sizzling and browned on the outside and cooked to taste, 3 to 4 hours for medium (155 degrees).
Step 5: Transfer the pork to a cutting board or platter and let rest for 15 minutes before carving and serving. (Note: A heavy cleaver is helpful for cutting through the backbone.)
Step 6: Meanwhile, make the Red-Eye Gravy. Carve the roast and serve with the sauce spooned over it.
Note: A pork loin roast is a primal cut that includes the rib roast, loin, and tenderloin. Special order it from your butcher.