I hope this demonstrates that standard rocker gear and a fundamentally standard oil system can support high performance:
https://www.facebook.com/photo.php?v=553759521342786
This was achieved with no external filter, no external cooler (therefore no leak-prone external oil lines), no fancy fan, no funny business, standard rocker gear and pushrods (of course set-up to suit).
CNC-ported 044 heads, 1916cc, Webers, counterweighted VW crank with prepped standard rods.
Engine carries a power pulley and a small (500mL) deep sump.
And it was 40+ (105F) degrees!
Keep it simple, build it right, and it will survive