If engine swaps are truly confirmed, I think I’d mostly do swaps not unlike the Beetle we saw in the trailer, where I’d specifically do swaps that add notably more power to a car. For example, I’d likely put the Honda S2000’s engine into the S800 or S660, and similarly, I’d consider putting the Alfa Romeo 8C Competizione’s engine into the newer (but otherwise less powerful) 4C.
Yeah, generally, I don’t really plan for any truly crazy swaps, like putting a rotary into a Mazda Roadster - just mostly ones that’d be between similar models, or manufacturers in the Beetle’s case. Indeed, it could be a lot of fun putting a Supra (A80) engine into say, a Daihatsu Copen, the Sports 800, or the 2000GT, and then tune the heck out of said engine.
EDIT: Definitely gonna do a swap on cars with both lower power, but also have engines that have less ability to be tuned. So that likely means I won’t be swapping say, the Supra (A80), the Sprinter Trueno/Corolla Levin, or the Skyline GT-R (R32), for examples. There’s likely going to be more than enough to work with when it comes to tuning those particular engines. I feel that swapping out a less common sort of engine like a boxer or rotary for a more traditional layout would be sacrilege, too - unless it was one of the same sort, like putting an RX-7 engine into an RX-8.