dry shot adds just nitrous so u need the extra fuel from ecu/injectors.

wet shot adds fuel with the nitrous(generally thru the same nozzle),so generally negates the need for ecu work/injector work.

dont know much about d series engines but u might get away with a 50hp dry shot(my guess,this would be the absolute limit,so,i wouldnt chance it),but anymore & u definitely need the extra fuel work.