[78w72]

I had the original comp roller lifters for a couple years on a aluminum head 467 with OF cam, they were noisier than I liked but was assured by comp & SD that the ticking wasnt a issue mechanically and wouldnt hurt anything. I was told to use seafoam too but that didnt really help, I just lived with it for awhile then asked about warranty replacement when the new "S" version comp lifters came out, luckily they were warranted & replaced, new S lifters are much better & only slightly tick when fully heat soaked on very hot summer days.

The original lifters specifically said 1 full turn past zero lash for adjustment, but the new S version said 1/2 turn, Ive read a few times where people where adjusting the original comp hyd roller lifters to less than the suggested 1 full turn which probably contributed to the ticking issues. Ive considered cliffs adjustment on the new lifters if they got any nosier but so far the 1/2 turn comp recommends is working ok, gotta expect some level of noise from these inconsistent tolerance lifters.

The biggest thing that seemed to help mine was using a thinner oil suggested by SD & comp, they both said to use a 10/30 oil to help with the ticking. You mentioned loose bearing clearances, what is current idle & hot psi with 15/40? Might be worth a try to use 10/30, if it provides decent psi at idle of ~20 and jumps up to 50+ hot that is more than acceptable for a street engine that runs under 5500 rpm and very well may help improve the noise. Free oil is great but if its not needed or causes other problems there is no reason to use it when good quality oils are availabole for like $20-25 for a 5 qt jug at walmart or on sale at other stores.