I had what I thought was phantom knock the entire time I owned my car. Made 285HP on pump 92, knocking like crazy. I tried the race gas at Bobby and Steve's, it didn't help at all.
I went E85 and made 366 on a half assed tune at nearly the same boost level (~23-25psi), with zero knock. The complete lack of knock is what I believe made the huge difference. On 92 I was almost always seeing 40 counts.
Here's some charts. Don't mind the shitty HP curve, it was a shitty tune we did just before the dyno day, had some issues. And that shit tune still did better then the 92 tune that was actually done at a shop.
Before:
After:
Hybrid Mode
