grampi
Supercharged
The ignition is fully electronic, so if the ignition timing is out of whack there would be something seriously wrong. If the cam timing is out by much the engine will likely not run at all and things will be severely broken inside.
You say none of the throttle bodies have capped vacuum ports, are they open into the throttle bore?
All 3 throttle bodies have 2 vacuum lines each, and the other end of all 6 of those lines connect to something like junctions under the tank. None of the TBs have a plug or an opening into the bore.
Isn't engine timing changed by the map?