Hello g community! Today i had my Berk HFCs installed today by a muffler shop hear in Dallas. They are not only cheap in cost but do a good work. I however have one concern...

When I finally received my car back after getting the HFCs in, there is a terrible "ehhhh" sound coming from the new cats when Im accelerating. The noise isn't bad when standing outside the car, but when inside the car the noise is unbearable.... Im pretty positive that they used the new gaskets that were included, but if they didn't, could this help solve this weird sound? Is this rasp? Drone? Do the HFCs have to break in?

Any help will be appreciated...

I can definitely feel a power and torque increase, just hate the sound from inside the car.

The HFCs shouldn't be hitting any part of the car...

Thanks