I have this problem and it's only the second time that I have seen it. The other guy switched to an aftermarket PCM so it was never resolved. The problem is that we are getting 2* less timing in the logs than what we are commanding in the tune. The car does not have knock sensors and is tuned in open loop speed density. All the modifier tables are zeroed out. I'm thinking that perhaps it's a mechanical problem. Just trying to understand how it is that the scanner determines how much timing is actually being run. Guessing cam and/or crank but would like to know exactly before I start switching stuff around.