Originally Posted by swartlkk

It must also be said that many times, the increased timing advance was programmed into the PCM'* at the buyers request. If you wanted a PCM to be programmed for mods that you were going to add later, you could request a PCM be programmed to best take advantage of those mods even before putting them on your car.

If you do too much ramming around with it before putting on the mods that support the programming, you can expect things to go wrong (ie, detonation that could chip a piston). I would bet that many of the people that were having problems were thinking too far ahead in their PCM programming. You shouldn't have a PCM that is programmed for mods that aren't there yet unless you know for sure that they will be there in a matter of days (not weeks) or take it easy between the PCM upgrade and the rest of the supporting mods.