Coil Spring Set: 70-81F LOWERED 2 inch (52mm)This is a precise USA made set of coils that are 2" lowered from factory settings. If you have a small block Chevy in the Camaro or Firebird TA.. Hotchkis recommends the small block set. If you have a BIG block Chevy in the Camaro or Firebird TA.. or a Pontiac V8 Block or an Olds 403 in the TA we have successfully used the BB to stop the front end sitting on the deck. Pontiac engines are heavier then Chev SB. You figure the way you want to go. A Chev