sure its the same weight, but the car will be still slow. im not trying to clown on Si's, but where im from they get smoked on a daily basis. its gonna take more than a b16 to make a coupe move. i agree w/ jus making use of the block. a b16 cable tranny doesnt cost much, and neither does the head. an ecu would be easy to find. ur prolly gonna spend only a 1/3 of what a gsr swap would cost.