When I was about 7 my brother and I both remember riding with my Dad in a 69 Ford pickup chasing down cattle that got out of their pen. One rogue cow got out in the middle of a plowed field, the Ford truck right on its tail with the 360 at full steam screaming across the feild trying to chasing the lone crazy cow. As I remember Dad almost had the cow pointed back the right direction when all of a sudden the engine pulled down a little then it was like the key was shut off, and cow got away. Lol. We asked Dad what happened, frustrated he replied the lifters pumped from floating the valves and made the engine shut down. He waited about a couple minutes, it fired back up and got back on the cows trail.... If he would have had the lifters set at the top of the preload the story would have ended differently.
Having the lifters set with almost no preload is the only setting that could have changed the outcome.
The only down side to running the lifter preload at the bottom of the preload is if you do happen to float the valves it has potential to go full stroke and have some valve to pistons clearance problems. Probably less likely to happen with higher bleed rates. The OEM lifters that have longer bleed rates would likely have more risk than a higher rpm lifter and a faster bleed rate.
I know of a builder that has “S” hylift Johnson lifters special made for .904” flat tappets, never seen them for .842” lifters.
The “S” rollers are rock stars to a certain point and then the dyno graph seems to get wonky because the plunger seems to have to much pressure on it and can not control the valves. At least I assume that is what is going on. High rpms the short travel set ups seem to be the best. Short travel sound great until you see the 70% decrease in the service life. Lol
I was not aware Hylift quit making the “S” hyd roller. I thought Hylift has not made any Pontiac lifters for awhile mostly becuase there production line was behind.