It has been discovered that a knock channel setting of 168 decimal in vemstune can result in spark angle being *added to* relative to the main spark map. This occured on a 2.7t engine running vems 1.1.88. See the .vemslog here:
http://www.efiexpress.com/downloads/v3.3_n003146-2011.06.07-12.22.44.vemslog
note where the engine hits 1.3 bar boost, the spark map requests approximately 14 degrees ignition timing, however the spark angle reading in the log reports over 25 degrees. This resulted in burnt pistons on 2 cylinders (and a junk engine block) on the customer motor. No knock settings imaginable should result in knock timing increasing over base values, naturally...