hi all just fitted a front mount intercooler equal length headers d cat straight through 3 inch exhaust induction kit to my 96 jap import impreza has a z4 epu with a bozz speed chip but car seems to be back fireing when you come off boast any ideas on how to stop this

 

get it remapped

 

thats just over fuelling on over run

 

Exactly as post 2. With all these mods you need an ESL map or an aftermarket ECU like Apexi Power FC or Simtek.