I have had knock issues since I took the performance stuff off. Turbo, headers downpipe. I had converted to 87 ecm. Most of my chips seemed to have too much timing. I could hardly go past 5# of boost and get knock. I've gone back and forth with chips and computers 84 and 87. My question is, should you notice a difference right away. I'd drive a few miles and not notice anything. I got busy and left the 84 computer and stock chip in. After a few days it is now much better. I back up to almost 15#s and just some knock in the green (caspers knock guage) Scan master won't work with 84 ecm. I also bought gas at a different place. So could it be the gas, or does the computer have to learn things over, so to speak. I do unhook the orange plug by battery.