the water hardly touches the coating surface, and 'bounces' off
super-hydrophobic as mentioned in this article
Superhydrophobic material repels water so strongly it causes liquid droplets to BOUNCE off | Daily Mail Online
Possibly as used by Soft99 for their wing mirror product (video...
If you are doing a rebuild or engine repair, before considering re-bore and oversize pistons how about block repair and coating?
Cylinder bore coatings by Poeton – Apticote 2000
Before
After
Poeton Apticote Ceramic 2000 is the premier cylinder bore and cylinder liner coating...