[DD (CA)]

Hello and sorry for the LONG, vague post (for builders) or too tech post (for those like myself).

Subject motor:
289 hid flat tappet
Stock heads: ported, machined deck*
Cam: Comp: 256XE+Ni treatment
Springs: Standard, single coil
Rockers: Comp Mag.Plus roller tip

Longer story behind motor, but should be NOS, stock and virgin cylinders.

This week is the third time I've had my guru go back into it. First time, after 20min, car would idle extremely rough, any throttle and clutch out would die; would not get underway. Motor pulled. gone through. Machinist "no damage, see nothing wrong here." Motor back in. 2-3 drives; 10mins long, clatter-clatter.

Pull VC, few arms noticeably loose, by hand. Lock nuts on screw down studs. Ran motor, adjusted. Full loose > turn to quiet > 1/2 turn and polylock. Motor quieter, but after 20min drive becomes louder clacking again.

So back we go....

Pull VC, 3 arms really really loose, polylocks not loose. hmm. Remove arms. Galling at ends of pushrods (light, standard, non hardened(?). Most arms clean 100%, some very light marking. Going to reuse.

IM removed, new lifters being placed in and hardened pushrods (TFS 6750*). My guy did note the wear on valve pin was slightly toward exhaust (outboard), so moved from now measured 6.785" (was 6.8") rod to shorter 6.75 rods to center wear.

The lifters were not noticeably gouged or worn flat/concave. Therefore, the assumption is that cam is still OK. There were a couple lifters with linear marks barely, but the thought is this likely occurred when rods did not turn freely due galling. (All but 2-3 rods had damage...) Rods not bent or at least not easily noticeable with table test.

Lifters not considered to have collapsed.

Called Comp to ask "is it possible to have excessive pushrod wear, but not be due to damage from a cam?" Answer: yes, sure.

My question is... I'm not so totally sure this is all we should be doing.... I've seen some posts on here with 'lucky' folks having bent rods and suggestions were largely to replace and try again. Which is what we are doing. Anyone else care to chime in for what else I might wish to look for while IM is off...?

Thanks very much,

DD (CA)