Adding headers may pull down some of the torque until you get the other mods under the hood, however spinning is spinning and you'll still be able to smoke tires if you add headers a bit on the early side.
As far as low end torque. I like it too. There's a resulting problem from it though. The transmission hates it. Our pcm's have programming called torque management to try and keep us from enjoying low end torque in the 0-60 area. The problem is..if you frequently like low end torque, sooner or later your transmission will give you a lesson in walking.
