https://static.summitracing.com/global/images/instructions/lun-02002.pdf
Lunati recommends .020-.060"
Many hydraulics only have about .180-.200" travel, total. The more a spring is compressed, the higher the stress in the spring. Higher stress = shorter life. The lifters probably collapsed as a result and resulted in the ticking.
Non adjustable rockers are great for OE, mass-produced applications. Not so great for an aftermarket combination of parts unless everything is thoroughly measured during assembly.
