That makes sense, cause i've got Apexi WS and I can't hear vtec kick in, but on my buddies '99 GSR he has a test pipe and no muffler, so you can definitely hear it. It probably doesnt help that my vtec doesnt engage until around the same time as the secondaries open up anyway (somewhere around 6000 rpm). Oh yeah, what is the benefit to having vtec kick in this high? It was tuned that way when I bought the car.