Silencer certainly works great at silencing the induction noise, but it restricts air flow too much.  I am going to try a different sized one.   They advertise it not reducing horsepower... I have to disagree.  The motor sucks alot of air.  Could certainly feel the draw as I was installing the silencer on the velocity stack.  Back up to 9350 on RPM's.  It was the coupler.