need to watch retainer to valve guide clearance and piston to valve clearance
i run a .485 lift roller cam in my 318 with stock untouched 360 heads,(88-360 headed 318 cop engine never been apart yet)
i swaped to comp-901-16 springs and used all stock retainers,valve seals,push rods,rockers
lunati voodoo roller cam 60710
258/264
.485/.485 lift
work great for a daily driver in a stock engine in a stepside truck
the comp springs drop on and .485 lift works great,IMHO
if it has the rotators on the exhast valve,drop those and use 8 more intake retainers and spring
the rotators make the exhast spring and clearance less in stock fourm..will not take much lift with them on the spring