E30 generation (1986–1991) BMW S14 four-cylinder engine, a high-revving DOHC E36 generation (1992–1999) S50or(S52engine US), 6 Speed gearbox, engine capacity raised to 3.2 -intake mods, fast road camshaft and supercharger kits make good power. E46 generation (2000-2006) S54straight six...
Smaller engines do not provide much of a return in terms of power so start with a bigger engine. Engine swaps are a good option if you have a small engine size. The M4 Engines. The F82/F83 M4 uses BMW's S55B30 twin-turbo straight-six replaced the earlier V8 used in the M3 but p...