Cam for torque question

Lustle said

That XE268H should make tonnes of vacuum. 15.5 inches at 850 idle.

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FWIW, we have a Crane Z268 in a 340 and have 14-15 in idle vacuum at 850 RPM. That cam has slower ramps than the XE and a 112 LSA but 9" at vacuum is indeed low. All the comments as to tune are spot on. If you are happy with the car's performance (as it seems like) then I would not change cams before getting other items straightened out. As suggested, the the PCV may be wrong for that cam and may be opening up wide to the higher cruise flow levels at below 15" and throwing the idle setup all off. A stock PCV will have that problem so should be replaced.

Then a cam change would be in order if you wanted more MPG, for example, or more low end, and were OK with a bit less top end. But I see no reason it can't still rev to 6k+ with a step or 2 down in cam; the heads are decent flowing. Your SCR is not excessive to start with so it can stand some more DCR.