Hi, and welcome to Tropical Fish Keeping forum.
First I am going to suggest you read the "sticky" on cycling; stickies are important or very useful articles on this and that which appear at the head of the relevant section of the forum. This one is at the head of this section, Freshwater Aquarium, but here is the direct link: http://www.tropicalfishkeeping.com/f...m-cycle-38617/
Cycling can take from 2 to 8 weeks normally, under adequate conditions. I take it there are fish in this tank. If the ammonia is really at 4 I am amazed they are still alive; are they showing signs of stress (rapid respiration, red gills, hanging sort of gasping at the surface for air? Most of us recommend partial water changes daily to keep ammonia below .25, same for nitrite when it appears. The internal damage that can usually occur with ammonia poisoning may not kill certain fish immediately, but can cause other health issues and premature death later on.
What water conditioner are you using? Some detoxify ammonia, one (Seachem's Prime) also detoxifies nitrite. This would help during cycling. By ACT test kit do you maybe mean API? If yes, it is a reliable kit (the liquid one).
As there are fish in the tank, and no live plants (these aid in cycling) I would strongly recommend a bacterial supplement to aid in establishing the bacteria. It is what we call "seeding", when live bacteria is added to jump-start the bacteria colony in the new tank; bacteria from existing established tanks is often used, by using "dirty" filter media, wood and decor moved over, gravel; but in the absence of an established tank for bacteria a supplement will do the same. Seachem make one called Stability, I have used it and I know it works, it is 100% live bacteria. Tetra also make one called SafeStart, it is also 100% bacteria. There are a couple others that may be OK, but these two I recommend. A small bottle will suffice, you only add it daily for a week or so.
I or others may have more comments when we know the above info.