air or fuel, what am i running out of

Seems like a lot indeed... but I used to rev to 8k+ all day long with hydraulics in a Opel cam-in-head engine. Presumably it is the lower weight of the smaller valves and no pushrods....and better back-in-the-day lifter quality. My 351C went up to about 7k with hydraulics.... with the 1.73 rocker ratio and run-of-the-mill dual springs, with stock rockers and pushrod; lifters were smaller (so lighter) and the cam profile was slow.

I have to wonder what effect the lower valve weight in the smaller 318 valves would have on the upper rev limit?