tappets are bleeding down a little. it doesn't take much bleed down with a hydraulic tappet to get pretty noisey. i'd check the preload; you may need more.
Here's hoping you are right...so I don't need to pull the intake (stealth hds), replace lifters, and do a break in. Plan to remove valve covers, look for anything obvious, then check each lifter at cam base circle for slop with cold, not running engine. From my build notes, used custom length pushrods sized for .020 preload.
If your clearances allow, maybe try a 10-30 and see
if it pumps up more quickly??
Tried this, the rattle got worse IIRC.
