It is tru 1zz engines run on a lower compression ratio but its slower. 2zz may be a bit harder to tune but its well worth it. A turbo kit can get uup to 260 hp but the the turbo has to spool first. I would go with a supercharger for gt-s because you'll get acceleration off the line and then the once the lift kicks in even more acceleration. Here are links to both turbos and the Supercharger for the Gt and Gt-S.
TurboKits.com - 00-05 Toyota Celica GT Turbo Kits, 1ZZ-FE
TurboKits.com - 00-05 Toyota Celica GTS Turbo Kits, GT-S 2ZZ-GE
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