My car made 437whp at 18psi on pump 93 with gt675rs turbos. I told the tuner that I heard that these engines start getting knock past 17 psi but he said he didnt hear any. He used the knock headphones and everything. He said I was good at 18 psi.
Follow Ups
Just got back from the dyno - VERTTZ18:57:16 07/09/12