Nitrous Oxide System - NOS GM LS Wet EFI Nitrous System (05164BNOS)GM Multi LS Installation Notes: This kit retains stock throttle body location and orientation using a 1 2 inch billet aluminum plate. Power levels up to 250 RWHP do not require injector upgrade, however, the total fuel supply system must be sized according to expected power levels. Recommend 1 step colder spark plug up to 150 RWHP, 2 steps colder spark plug on 200 and up RWHP shot. NOS GM EFI Nitrous Systems are the best way to get a power increase in