I don’t know a ton about foreign motors other than surface level stuff like the 2JZ, Wankel, etc. so please forgive my ignorance outside of US motors.
However, in my eyes, it doesn’t get better than the simplicity and easily available power of the SBC, BBC, and 6BT. What are your all time favorites and why?
Volvo redblock is the original great 4 banger.
I had a slightly modified B21FT that had my station wagon keeping up with Mustangs and Cameros on the highway that were 30+ years newer.