Cool car, btw.
The old Mopar solids 528-557-590 are noisy because the spec is .032 lash.
Modern solid lobe profiles run much tighter lash.
For example, the Ultradyne/Bullet solid flat tappet cams run .016 lash.
Similar tight lash settings for Comp FL, SQ, MH, MF, and MM.
- Big difference in valvetrain clatter at .016 compared to .032+.
As far as reliability goes...you are just as likely to rip the lobes off of the cam with a hydraulic lifter as a solid if you don't have any zinc in your oil.
No matter what design you go with, I would have a custom cam ground up for your application.
Call Hughes engines, or Tim at Ultradyne/Bullet, or Dwayne Porter at Porter Racing heads, or Brian at IMM engines.
This is the short list, there are many other very good builders on this board who could guide you, also.
You will likely get more answers on this topic over on the race section, as there will be more engine builders lurking.
