Ive built a 245whp bseries before and its not easy. below is links to my build. Im sure the motor had more in it w/ better cams . I sold that swap for a K20a swap w/ IPS k2 cams and a DTR header which almost ran as fast but w/ 1/10 the mods .

https://www.tamparacing.com/forums/h...-i-killer.html

https://www.tamparacing.com/forums/h...-part-2-a.html