Engine

I don't think the Mitsu's can run gas, Im guessing that is where all this is going. Spare parts would be cheaper and more readily available. 3.0 Mitsu were not exactly a powerhouse, and you had to get them screaming to get any life out of them, drank like a fish too

Power/Torque are not the be-all-and-end-all. It is where they occur in the rev range. 3.8 a lot lower revs than the 3.0/3.5

the 3.8s treated me well when i had them, a late build VN then a VR
Once saw one with a blower and injectors done by Supercharger Technology Aust., they were boasting better specs than the HSV of the time.