Hi, I've recently acquired a GT/CS mustang with a 289 4 barrel auto. The current engine unfortunately has had it after sitting in one place for over 20 years and needs replacement. Would it be a crime to replace the 289 with a 390 also from the same year? As I understand it the 390 was a option at this time. What sort of modifcations would be involved in installing this larger engine? upgrade for brakes, transmission I assume. Is it too much effort ? should I just replace it with another 289? Any advice appreciated.
regards
regards