The VF22 came out on the my96 V2 STI, good turbo and much better than the TD04 you had, it'll handle 18 PSI all day but I'd say you probably need a re-tune by the sound of it.

Have you checked every vacuum hose thoroughly?

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Beaten up old 98 Gen 2 Liberty, 13.0, stock V3 STI running gear.
07 Transit motor home
69 VF & 70 VG Valiants needing full restoration
Yamaha Zooma 50cc rocket hopefully going with the Transit.