You might just have a weak ass D series motor :chuckles:
VTEC kicks in really loud on my car at 4500 rpm. I have a GSR ECU, Greddy Evo Exhaust. You notice it and yea, it kicks you back. You might want to check your oil. VTEC relies on oil pressure, engine temperature, and the ECU programmed to engage it at a certain RPM, etc.