I had my car tuned pretty well with MSII V3, 2.8xx code. I'm using the factory VR sensor and distributor, triggered by the MS. Initially I had a trigger offset of 35*, so that it would fire mostly on the center of contact on the rotor. I recently switched to MSII extra, the most recent code, and whenever the timing increased to 35* it would misfire badly, I think this is due to the trigger offset of 35 degrees...
Suppose my minimum timing is 15*, and my maximum 38* including cold advance, etc, and assuming I have the flexibility, would making my trigger offset just below 15* or just above 38* provide more accurate spark timing? 38* would be a little easier to obtain, since its alot closer to the current offset, but if being closer to the minimum timing would help accuracy, I'd like to try that.