1. Strip husks and silks from 6 ears corn (7 to 8 in.).
2. Prepare barbecue for direct heat.
If using charcoal briquets, cover firegrate with a single, solid layer of ignited coals; let them burn down to desired heat. Set grill in place and measure heat.
If using a gas barbecue, turn all burners to high and close lid for 10 minutes. Adjust burners to desired heat. Set grill in place and measure heat.
When grill is medium-hot (you can hold your hand at grill level only 3 to 4 seconds) lay corn on barbecue and turn ears as needed until hot and speckled with brown, 10 to 12 minutes.
3. Rub corn with lime wedges and sprinkle with salt to taste.