gruntguru wrote: ↑
Tue Oct 05, 2021 9:42 pm
godlameroso wrote: ↑
Tue Oct 05, 2021 12:59 pm
The hotter you run the CC, the more valve seat erosion happens. When the valve seat erodes the valve stem becomes taller relative to the rocker arm. Eventually the valve seat erodes to the point that the valve no longer fully closes because the clearance to the rocker arm has disappeared. . . .
You are suggesting that valve clearance is not adjustable. I find that unlikely.
The other consequence of such a high degree of seat erosion is a problematic reduction in gas flow. Again - unlikely that they have seat erosion as bad as that.
It's known if the valves are directly pushed by the cams or there are rocker arms?
When Honda tightened a bit the distance between the camshafts, it came nearly clear Honda should be using rocker arms.
I don't know if Merc and / or Renault are using hydraulic or solid tappets / cam followers... Or are also using rocker arms, as some suspect is Honda doing.
In any solid (not hydraulic) layout, I don't find reasons for F1 manufacturing tolerances not being sufficiently accurate to get rid of any adjustment mechanism (and potential failure, and greater moving masses).
If I were designing an engine as "perfect" as those, I would try to avoid it by sufficiently adjusting the dimensions. In road engines, cam lifters adjustment is essentially to account for mechanical wear of the cams and the valve stems and I suspect that also for manufacturing economy reasons (cheaper to have not so perfect rocker arms, but adjustable).