Also important to understand my application is very much different than Plimmers. Its just really nice to see people with info give it back to the community.
Setting a intake cam retard ceiling. Boost works better with bigger intake cam durations, you can continue higher RPM retard to reduce the exhaust reversion and not sacrifice the compression stroke length as much. Ideally you get a gradual slope from starting advanced to furthest retarded position at max RPM. This doesnt mean keeping a 40* swing, but a smaller advance-retard swing with a larger duration camshaft. That is the sacrifice push rod motors make, and VCT engines are no exception, once you are at a "big cam" it just doesn't/can't move. If you are having to advance the cam in the higher RPMs(15 back to 10) you ran out of camshaft in the backpressure/ compression stroke fight, or exhaust back pressure is too high (until waste gate opens). Sometimes just taking a small diameter, lengthy turbo back exhaust off can help significantly unchoke the turbo/s. Cat's coming off from behind the turbo are also a large relief of back pressure.
Swinging the cams 30* in a 2k rpm window seems like something you would do to limit cylinder pressure after it has built too quickly. Detonation limitation or locking the timing can create this illusion in the dyno numbers, because torque is relative to actual sparks distance from MBT spark. MBT spark is moving along with the cams. Static bracketing them is the only way to eliminate that as a variable.
Attached is the dyno showing intake at -20, 0 and 20, with exhaust held at 10. For all my intake tests I held exhaust at 10 and then made 7 runs from -20 to 20 on the intake, moving it 5 degrees each time. I then logged my MAF at each 500rpm point and selected the setting with the highest MAF reading for each. Like I said, there is a little fuzzy logic needed since intake temps also change so power and MAF comparisons are difficult.
One more comment related to the dyno chart I posted, the WG duty cycle was identical in each run, so I don't know why the 1psi difference in boost between the runs. Intake temps were similar, so maybe the cam timing was causing this. I hand wrote other 7,000rpm parameters so you can see what changed each time.
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