I'd say it's your timing chain, tensioner & chain guides. Check your tensioner & chain guide's. While your there, I'd be pulling out your balance shafts also= add a bsd plug too. It'll hold another 1 qtr of oil, which is a good thing. How many miles?
Introduce Mr. Torsen to the mix
Bigger brakes then you- D23 crew- D-Tech- Sedan Revolution= #131