I have a question regarding the relation between bore size and the valve float. Why changing the engine’s variant bore size is not affecting the valve float, while changing the family bore size is? For example we have three engines:
Family 1, 80mm x 80mm (bore x stroke)
- variant A, 80mm x 80mm (bore x stroke)
- variant B, 70mm x 80mm (bore x stroke)
Family 2, 70mm x 80mm (bore x stroke)
- variant A, 70mm x 80mm (bore x stroke)
I understand why 1A would have more valve float compared to 2A. Larger valves etc. But why 1B has the same valve float as 1A? As I understand/imagine 1B should have the same valve float parameters as 2A, as the valves, springs, rocker arms would/should be identical in both 2A and 1B (might be not true for pushrod engines). The cylinders would have the same shape, but they would be more spread out, so the camshaft(s) would be longer, and maybe a bit thicker (to increase stiffness due to increased length), but this shouldn’t affect valve float.
Am I missing something? Or is this is a bug?