BasePart.CollisionsDisabled, BasePart.VoxelShadowsDisabled

First off, lighting is cheap. If VoxelShadowsDisabled is implemented, it probably won’t be for performance reasons.

CFrame should be one of the fastest properties to set because it doesn’t cause a recluster. It might cause some kind of physics update, but have you checked the microprofiler?

do this instead

part.CFrame, part.Size, part.CFrame = part.CFrame, newSize, CFrame.new(3.4e38, 3.4e38, 3.4e38)