i would go with the T51 SPL BB. it has 11% faster spool up time than other turbos of same size according to HKS. i have seen pictures of the JUN Z engine and they have transformed that engine to a single throttle just to fit the turbo and made a custom ex man just to fit everything in. T51's are rated in 1000ps each... if you are trying to do something different you are... let me know how everything is going cuz im interested!