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?
My personal favorites may not be the best but I like them,
V8: LS3, sounds great, huge aftermarket, capable of some ridiculous power numbers.
V6(hot take): Hyundai’s Lambda II, moddablility isn’t great, but imo it is the best sounding V6 you can buy and with 350hp, one of the more powerful NA V6s commonly available.
I4: might be biased, but it’s GM/Saab’s LSJ, stock internals proven to handle over 500whp, record on the block is 898whp. Comes stock with a supercharger in American form (Cobalt SS/Ion Redline), Turbo in Swede form (Saab 9-3), enough afternarket to make it turbo or even twincharged, and it can be paired with 5 or 6 speed manual transmissions
I love 5 cylinders as well but they’re getting hard to find :(