5 engines which could be a good upgrade to a VW Beetle

One of the most iconic cars, the Volkswagen Sedan/Käfer/Beetle/Fusca is recognised among many features for its flat-four air-cooled engine. However, it's a suitable platform for engine swaps which are likely to improve its performance, fuel-efficiency and provide auxiliary power for some comfort features with fewer stress than the old Boxer would. Among some engines which could be a good option, at least 5 can be highlighted:

1 - Renault K-Type engine: since it shares the bellhousing pattern with the old Cléon-Fonte and the "Energy" engines, and the Cléon-Fonte had some derivatives fitted to Volkswagen models in Brazil from the late-'80s to mid-'90s, a K-Type engine swap doesn't seem so much of a rocket science task;

2 - Volkswagen EA211: just like its predecessor EA111, the EA211 is a more compact alternative to the EA827 and its subsequent replacements. With the 3-cylinder 1.0L versions available either with natural aspiration and port-injection or turbocharging and direct injection, while the 4-cilinder takes the 1.2L to 1.6L range with the same availability of either natural aspiration and port-injection or turbocharging and direct injection, there are plenty of options from a more frugal to some spirited power and torque figures;

3 - GM Family 1/Family 0/Small Gasoline Engine: tracing from the use of  Chevrolet 153 engines for swaps into Volkswagens in South Africa to the present-day downsizing trend which renders some turbocharged variant of the smaller engines available on newer Chevrolet cars and crossover SUVs suitable to perform basically the same duties the old 153 would perform, it wouldn't really surprise me to see some random Chevrolet engine ranging from 1.0L to 1.8L also either naturally-aspirated or turbocharged being considered as a suitable option to swap into a Beetle;

4 - Toyota TR engines: tracing from the usage of the Y engines for repowerings into Kombis in South Africa and some Asian markets, with the TR being its replacement for some applications, it's no surprise the 2.0L 1TR-FE would be an interesting option for performance and long-term reliability while the 2.7L 2TR-FE could seem quite overkill yet tempting for a sleeper;

5 - Fiat FIRE engine: ranging from 0.8L to 1.4L and with turbocharged versions available within the largest displacement, it's also widely used with alternate fuels such as ethanol, Natural Gas and LPG. Requires an adaptor plate to be coupled to the original VW transaxle, but it's no rocket-science.