Only changing the thermostat to a cooler running run to bring the temps down. Changed the oil over to penrite HPR 30 minreal stuff which is great stuff and presto the lifter noisese were gone.

valvoline and penrite running in oil is straight 30

could this be the same problem im having with my EF XR6 i put in a rpd stage 3 cam/springs and new lifters and got a horrable tick that wont go away
How much should it cost for good grade mineral oil?
and how many litres to do an oil change?
the lifter cleaner mentioned is it worth buying pro's/con's if any as im wary of engine addative's unless it provides more KW lol

If you have just put new lifters in why would you need lifter cleaner??