Right and if you are setting the ignition timing explicitly, you don't care if it messes up where you land on the main tables. It owuld be easy enough to just have a separate small subroutine on the load of the scaling value from memory to pull the normal value or the modified one based on your ALS flag. The only problem I see if the ECU only samples the scalar once during init. I can't remember if that is the case or not. I don't think it is.