PLEASE READ MISSING Looking for exhaust mod?

I had this mod that added loud exhausts. It was some two letter name like RK or something and the exhausts added pops and bangs and was available on every car. The cars that had it that I have saved no longer have it and I cannot find the mod anywhere. Anyone have any idea what it was? It was not JK's tunable exhausts. It was a standalone mod that was configured. This is config data from one of my saved cars
"vivace_exhaust_exit":"vivace_exhaust_exit_double",
"vivace_exhaust_i5_2.5_petrol":"engine_I5_exhaust_st1_RK",
"vivace_exhaust_tips":"vivace_exhaust_tips_alt_black",

See it is RK! Don't see anything on their profile though.