How do i make moving part positioning work in-game?

I made a script to make a certain part move at a speed. The part is anchored and non-colliding. However, when i play the game, the part moves horizontally, but bumps really much up and down and when it encounters another part, it goes up so it doesn't touch that other part. I just want the part to keep going through the terrain and other parts... How do i make sure the collision-problem is gone in my script/game?

local Bottom = script.Parent
local StartPosition = Vector3.new(-0.425, -12.332, 991.53)
for i = 1,1000 do
	wait(.01)
	Bottom.Position = StartPosition + Vector3.new(0,0,i*-5)
end