Some engines are just better from the factory. Every now and then the parts on the assembly line sort of 'line right up' and you get good stuff. Maybe all your intake ports were lined up good. Perhaps the extrude hone job was better, maybe you just got a good y-pipe and exhaust manifolds (meaning less welds sticking up in the flow area).
Keep in mind that the 'effects' that helped you be 7-10HP better in N/A mode are now being magnified by the vortech. Double the base power over your counterparts.
warmonger
Former owner of '99 CSVT - Silver #222/2760
356/334 wHP/TQ at 10psi on pump gas!
See My Mods
'05 Volvo S40 Turbo 5 AWD with 6spd, Passion Red
'06 Mazda5 Touring, 5spd,MTX, Black