[cnavarro]

I wouldn't ion nitride them without checking the rockwell of the rocker and cam lobe and make sure the spread is idea. Cryoing on the other hand, every engine component can benefit from cyroing, especially ones that are cast. DLC is very expensive and I would find another place to spend my money and just use an oil with sufficient Zn and P :-) We reserve DLC for engines where every last iota of HP is being squeezed out OR we are overbuilding an engine for uber-longevity.

The issue with the roller rockers on the 914 are that they do not oil the valvetrain with exception where you have sustained high rpms. Any customer of mine who uses them I more or less state that they need to fabricate oil squirters for the rocker box to satisfy the need for proper oiling. I learned the hard way when a low rpm street engine of mine ate up valve guides and ended up seizing an intake, and doing lots of damage along the way.

OHC engine inherently have less frictional losses than a pushrod engine, so i'm not sure what gains if any would be had with roller rockers.

QUESTION? Are 911 rockers self oiling or pressure fed? I've never held one in my hand, so I can't answer that myself.