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hey guys. i have a rb25det s1 going into a cefiro. i want roughly 400hp.

now the questiion. im getting a hks to4s turbo with a .73 (roughly that size rear) turbo and i want to know if this is capable of 400hp at the wheels. i know the turbo is old but it has just been rebuilt and its the right price. i originally bought a garret gt3082r with a .63 rear for my rb20 but decided not to whip a dead horse. i read that this turbo has compressor surge issues on rb25s????

anyway if some one could throw some knowledge my way i will be cheering.

Steve.

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yeah i know its not the very best option out there in terms of response but aslong as it gets going at a reasonable enough rpm i will be happy, aslong as it gets to the power level im roughly chasing. thanks for your reply dude.

From memory HKS T04S turbos were full T04's meaning they used a T4 turbine as well . T4 turbines were generally available in three trims N/O/P with the O and P trims (I think 69 and 76 trims) more common . The unique bit with HKS T04E's and S's was the turbine housing being "T3" flange and usually a smaller AR ratio .

As was mentioned these will not be real responsive because the turbines are heavy and the bush bearing center section not as free spinning as a BB cartridge . GT30 BB series turbos like the GT3076R are more modern evolutions of the older T series turbos .

A .

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