I have a 700r-4 trans. in my 82 z-28.......it is not the original trans. I am looking into getting a converter with a higher stall than stock, but i need to know the year and if it has 27 or 30 splines??? is there a casting number i can look up or another way to tell this info before i pull the engine???? any help would be great. (I have a 350 i am putting in and wanted to do both at the same time)