5 engines that would be interesting to swap into a RWD-converted Subaru Impreza

Even though much of Subaru's marketing nowadays has been associated with the boxer/flat engine and the all-wheel drive, its mechanics are not the easiest to struggle with. Even considering how the AWD may be a good sales point for the off-road themed XV/Crosstrek trim, which is the only available with the hatchback bodystyle in my country nowadays, it not being usually taken to serious off-roading may render such feature effectively useless for the average Joe. And honestly, due to the longitudinal engine position which is a must for a boxer, it may sound tempting to replace it with something else while also converting to rear-wheel drive only. I would at least take a look at 5 engines if I were going to do such:

1 - Cummins ISF2.8/R2.8: as it caters to Asian utility vehicles with engine bays quite cramped, even though a rear-wheel drive setup would also be required to ease the task of overcoming clearence issues in a Subaru, the Cummins ISF2.8 or its aftermarket-oriented R2.8 derivative available in the United States and Canada would be among my possible choices. I am quite partial to Diesels, and since the R2.8 is meant as an option to the gasoline-powered ubiquitous small-block V8 engines more frequently swapped into nearly everything, it seems quite down-to-earth compared to other engines which would require major structural changes to allow a clean-looking installation;

2 - Chevrolet small-block V8: an engine that nearly everyone loves. Either some first-generation one or the latest designs with some newer tech incorporated, the relatively compact packaging makes it a cost-effective option for high output;

3 - Nissan TB48DE: this straight-six masterpiece, which currently has a limited availability along the Y61 Nissan Patrol, has a strong aftermarket scene in the Middle East. Even though it usually has a quite conservative tune, turbocharging and other tuning allow it to exceed 1000hp with some reliability;

4 - Toyota 1GR-FE: not exactly a favorite of mine, but it also has some aftermarket support overseas which is also interesting when it comes to a performance enhancement. Toyota being a stakeholder on Fuji Heavy Industries also makes it sound more reasonable at all;

5 - Chrysler Hemi Hellcat: one of the most exciting engines in recent times, sure the Hellcat would be a good option too.