Looking for anyone to chime in. I have a stock 87 GN. It was in poor shape when I got it but have since tuned it and given it some minor upgrades (TT Chip w/ 60# injectors & AFPR, walbro 340 pump, hotwire kit). My latest runs with powerlogger has revealed boost levels at 20 - 21 pounds and with spikes as high as 25 pounds on 93 octane gas. During these times would get knock retard as high as 4 degrees and 02's would be in the high 700's to low 800's. Is that possible on a relatively stock engine?......