Preheat grill to 375°. In a large saucepot, bring a quart of water to boil. Add corn, cook for 5 minutes. Remove to cutting board; cool.
Cut each corn cob in half widthwise; slice each half into quarters. Place in a large bowl and toss in olive oil.
In a small bowl mix together salt, garlic powder, onion powder, pepper, paprika and cayenne. Sprinkle over corn and toss until evenly coated.
Grill each corn rib kernel-side down, until corn begins to char, 4-5 minutes. Place corn ribs in a large bowl; drizzle with melted butter and sprinkle with Parmesan cheese and cilantro. Toss to coat; serve with lime wedges and if desired, additional Parmesan cheese.