I PUT SOME BLACK GRAPHITE MOTOR MOUNT INSERTS, FROM ENERGY SUSPENSION, ON MY CAR WHEN I PUT THE JDM ENGINE IN MY CAR. I NEVER DROVE THE CAR BEFORE, BECAUSE THE MOTOR WAS BLOWN WHEN I BOUGHT IT. IT HAS A VIBRATION WHEN IT'S JUST AT IDLE, WHICH ON MY CAR IS ABOUT 750 RPM. IF I REV IT UP TO OVER 1000 RPM IT SEEMS TO LEVEL OUT. WOULD THIS BE BECAUSE OF THE INSERTS, OR SHOULD I LOOK ELSEWHERE???