I think my headgasket is leaking so while the head is off i was thinking of taking it to portflow for a p&p, valve job, etc. Currently jdm b16 skunk2 stage 2 cams toda header apexi ws exhaust aem cai 3" p28 Tuned on Crome this netted 182/128 on a dynapack. Im planning to go with an aebs manifold and itr tb at the same time to max the airflow. So how much should i expect? 10? 15? 20?