This may be an indication that you are due for new motor mounts. They are normal maintenance parts, and you might expect to change them some time before 100K miles.
Otherwise, as indicated, isolate the mounts with rubber. I had to do that somewhat with my True Flow intake setup as well. It was making noise as it entered the factory air box (True Flow uses the factory box instead of an air dam like K&N) and I used some self-stick rubber door strip to wrap around the tube where it enters the box. Helped a bunch.
Otherwise, as indicated, isolate the mounts with rubber. I had to do that somewhat with my True Flow intake setup as well. It was making noise as it entered the factory air box (True Flow uses the factory box instead of an air dam like K&N) and I used some self-stick rubber door strip to wrap around the tube where it enters the box. Helped a bunch.
