The specs for the original motor are between 96HP and 100HP at the crank, I estimated today that the weight for the car would drop from 2500lbs (original weight) to 1750lbs (estimated weight now) and with a motor with close to 400HP (anywhere between 370 and 400) at the wheels, I assumed that I should re-inforce the frame. At this point, I may as well box the frame, as well as re-inforce it just to provide addition support.