Bobs barramundi

Nearly everyone I meet with same setup have same problem you on the money mate.

Well 3 Katz my tuner has narrow it down to chain, since Atomic tensioner is ratchet even though its Hydraulic its still ratcheting, my noise only last upto 15 20sec very similar to yours but very faint maybe coz I have loud as exhaust. If you want I know bit of pain change the chain tensioner to factory tensioner and See if the noise still exist.

Hey 3 katz matey did you end up working out what the problem is? as I got my car back from tuner after all the work done to it and I have same noise on cold start but is very faint on last 10 to 15 second Max and boom goes away, but note its not as loud as yours though.