Engine-swapped NAs (Ford 5.0/302, LS, Monster Miata, supercharged) are an established niche that can sell strongly when done well, but the aged, low-rigidity chassis needs serious reinforcement (frame-rail supports, real roll bar) for V8 power, and built cars can be intimidating to drive.
V8 / engine swaps and chassis reinforcement
Mazda MX-5 Miata (NA) · variant