As far as turbos or NA's go? Well you know 87 was the only year for the turbo. I'm not sure if I ever saw a breakdown on NA Limiteds. They had there own unique VIN. The 84-86 will start 1G4M47 and the 87 will be 1G4M11. If I had to guess by going off of what I've seen in the boneyards and cars for sale I peg it around 25% to 35% of the Regals are Limiteds.