I'm running them, very happy with them but be advised you WILL need good shocks ,something adjustable as they react much quicker than steel springs. I used double adjustable QA1 shocks. I found 175 to lite might be ok for a SB though? ( I'm using a BB) , I replaced them with 225 lb rate ( expensive mistake!) You will also require different spring hangers as the springs are not standard e-body length.