If you put a tunnelram on a stock motor it will make a do gout of it. Tunnelram motors like a lot of rpm to work properly. 99% of the time, most motors willrun best with a single plane, single 4v intake on them. My cleveland is making between 575 and 600hp with one 4v carb on a strip dominator intake (it's never been dynoed, but based on the weight and et it should be in that HP range somewhere). I have a tunnelram intake I bought at a swap meet. I have never used it, and probably never will use it.

Tunnelrams wont directly affect reaction time, but they will make a motor lazy down low in the rpm range.