Magnum mount issue?

Its the same torque that was behind my internally balanced 340 thats now behind a neautral balanced 360, The balancer is all that changed, its not high end just a professional products but has the counter weights removed for an internal balanced engine, its not noticeable at an idle untill 1500rpm and when driveing its sort of up and down with rpm and load, lets up on shift points and with certain amounts of rpm. 1500 - 2000 is the worst though