sorry too keep going on rb25 head/rb30 short block no need for rb26 head($3000) rb25 head 450-500$ flow and diemensions very similar. rb 26 valve covers fit easy. rb 30 bottom 25 head ITS turbo = fun .just done one 657hp 21psi kind of wish i didnt very hard to drive but fun. dont be harsh im new here. if you were that way inclined!