[Mike Taylor 3601]

I agree with Art and Myron,in that one block to another or machine will be different, Myself I use break in rockers 1.2 some are 1.3 ratio sbc version lowers lift enough so does'nt see high spring pressure and is easier to swap rockers than springs.
The other day saw some imports that were supposed to be 1.6 that were actually 1.2 would made good break in rockers
Mike Taylor 3601