I have a 1986 gn,160 thermostat,TH downpipe,no cat,2 1/2 ATR exhaust,Lubrant 94 octane street chip,ATR cool air induction,Walbro 307,hotwire,adjustable regulator,boost commander,SMC alcohol kit,TL as my scan tool,and I always run Sunoco 94 and xylene so I have 99.5 octane in the tank.I have been having a hard time tuning for proper 02's since the addition of the alcohol.I use denatured alcohol.Here is where I am at now.I have a base fuel pressure of 42 pounds,21 pounds of boost,alcohol turn on at 10 psi,and pump speed at 5 1/2 to 6.Until the addition of the TH downpipe I was able to run the pump speed at 7 1/2 but it would be sluggish at this pump speed with the TH downpipe.Go figure.Anyway my best run has been 12.62 with the majority of my runs being in the 12.7 to 12.8 range.Here is the problem,when I leave the line my 02's are in the 838 range but at the end of the run they are in the 780 to 790 range.I get 0 knock.If I turn the fuel pressure down I get 2 to 3 degrees of knock and my top end suffers 2 to 3 miles an hour.If I turn the fuel pressure down and the pump speed up I run no better.Now get this,I can run 18 pounds of boost without the alcohol and get no knock.I then set my fuel pressure at 43 pounds and my 02's are great the whole run.This is in the summer weather my fuel pressure may have to change as the weather cools but that is just a tuning issue.I can still get in the 12's at 18 pounds of boost.Some of you who have been running alcohol longer than me,what do you think moving my alcohol turn on point to 12 or 14 psi would do to my 02's?I understand it takes the pump 1/2 second to spool up and I don't want to detonate.Any and all responses will be appreciated.Bruce