As long as this thread is revived...

3S-GTE is IMO literally a 2JZ on 4 cyls...both square and great to make power out of, but even though I'm a Toyota guy, I'd get the 4G63.

Dodge's 2.5T that was in the Caravan, Shelby Charger, LeBaron, and every other fucking dodge in the late 80s is awesome as well, as is their SRT-4 engine. 1.8T deserves much much respect, especially for the amount of power (let alone torque) that they can easily make. I'm surprised nobody mentioned the Porsche 4...I think it was in the 944 from the 80s? EJ25 also deserves respect, but I'm neither a Subaru nor a flat 4 guy, however you cant go wrong with companies like Volvo, Saab, and Subaru who offers damn near everything they have in a turbo version.

"Honorable mentions": SR20DET. Dont care for the bandwagon when I can get an engine thats already here in an equipped car and IMO better anyways (see Dodge Caravan, DSM, MR-2, Camry, Celica, etc.etc.etc.)
K24. "big block Honda 4", but still a Honda, thus little to no torque. No thanks.

Also, for those who said aluminum sucks for engines with forced induction...see the 1UZ-FE. kthnxbi