if you set them at 0.020 you wound be ok cold but you should know who s cam you have to get the lash rigth if you run them to tight you will take the cam out .and can check by seening to see if the lifter will compress. this can be done with the intake off or on but you need to take off one valve cover just do one lifter be VERY CARFULLY turnnig the nut on the rocker do this.DO NOT RUN THE ENGINE . if you turn one full turn and it move down without much effort then there is a good chance that it is hyd but if it stops then it is a soild .the rocker need to be up .no compresson on the valve spring .AND RESET THE LIFTER