Loud noise from the rear, please help

I just had BMR sfc, BMR control arms, BMR lowering control arms brackets and BMR adjustable panhard bar installed. My problem is that right after the installation I started hearing this noise from the rear right side of the car. Every time my car would pass over a bumpy road specially roads with small holes I would hear a thud like as if I had bad shocks. First I thought that the car wasn’t wheel hopping anymore so the sound must be from my tires hitting the holes harder due to better traction. My concern has now increased as the sound has gotten louder. Any suggestion what this may be, is this normal? Any help or advice is appreciated.
Thanks


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98 Z28, M6, Chameleon Green,
Whisper Lid, K&N, Slp Loudmouth DD, Eibach Prokit, BMR SFC, BMR Adjustable Panhard Bar, BMR Lowering Control Arm Brackets, BMR Control Arms, Pro5.0 Shifter, !CAGS, Blackouts, Chrome Shifter Knob, 18 Inch Polished Wheels.

my car does the same thing. After some research, it was my exhaust (I have a loudmouth too) that was hitting the axle under bumps.

Turns out that on side of my panhard had come loose. just got the problem fixed and now the sounds are all gone.

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98 Z28, M6, Chameleon Green,
Whisper Lid, K&N, Slp Loudmouth DD, Eibach Prokit, BMR SFC, BMR Adjustable Panhard Bar, BMR Lowering Control Arm Brackets, BMR Control Arms, Pro5.0 Shifter, !CAGS, Blackouts, Chrome Shifter Knob, 18 Inch Polished Wheels.