Golf is TSI
S3 is TFSI
Both are the same 2.0 turbocharged 4 cylinder.
Tsi means supercharged and turbocharged and came out with the 1.4 TSI Golf.
However VW call their Golf, scirocco etc a TSI when there is no supercharger. Confusing much?
2.0 Tfsi = 115 bar fuel pump, cam belt, K03 turbo...