Why Does The Size Of The Object Affect This Script?

blob.CFrame = CFrame.new(blob.CFrame.p, mouse.Hit.p)*CFrame.Angles(0,math.pi/2,0)
				local heck = Instance.new('BodyVelocity',blob)
	heck.Velocity = (blob.CFrame*CFrame.Angles(0,math.pi/-2,0)).lookVector*120
	local coru = coroutine.wrap(function()
		wait(.45)
		if heck then
			heck:Destroy()
		end
	end)
	coru()

I do not understand why this happens but If I set the size of blob to 0.7 the script runs as needs to it launches the part and then curves down. But when I set the size to 10 then it doesn't even launch. How do I fix this?

You can edit the "Weight" of a part by going into its custom physical properties and playing around with density; however, you may also add body velocity with infinite force to keep your part afloat.