its not an even swap for sure but i cant give you an exact amount... there are too many factors.. but the gain off the bottom end will improve your run times becasue banshees lack bottom end already... so the idea is to get that fuker moving casue you only got so far until a drag race is over... if your not getting into you power until half track you already lost the race... so yes id say its a substaual gain as long as its no some 1 mile drag race your doing...