I think the best case in point is newer wild street setups, like the 814ci N/A pump gas engine Hot Rod had an article on a few months ago. Because that particular engine was being built for street/strip purposes, and making I think north of 1500hp, they shortened the runner lengths considerably on the intake manifold so that it's low end torque was severely decreased so it had better manners. I'm not the most educated on tunnel ram intakes, but I think they are relatively well known for their top end, and hurting your low end power? Using this logic you would still think the torque would be increased down low, but they're are many other aspects that probably affect tunnel ram's design, like velocity, application, etc. In some cases it's probably too much, and its potential gains aren't worth its downsides. The intake is probably removing some restriction from a stock setup, but isn't delivering the necessary velocity with such long runners for the engine to perform at lower RPM, and the longer runners then being overkill. I hope someone else chimes in with more information than I know, and that can verify or correct what I said if need be.