@Abe_Leal3D A hoses silhouette where you can see the 8 sudes is much less visible than how smooth the curve of the hose is, which is why even a 6 side hose will look good with enough loops in the curve.
Whereas the bolts are seen head-on and their radius is small so they need more sides.
@henningsanden Regarding modeling,
-high poly models mostly only need to bake well, so floaters and other shortcuts are used,
-larger bevels than realistic usually for good bakes
-lowpoly mesh is king (as that actually goes in the game)
-lots of engine shenanigans,especially in custom engines