CandiMan

iTrader: (1)

Now I understand that these are the mods that "makes" HP, while the others just free up restricted HP (if I'm correct) All three are placing stress on the internal of the engine, due to the excess fuel/air mixture (bigger bang/force) Taking into consideration that the timing has to be retarted, and more fuel added, do these three HP making mods affect the engine in different ways.

1MAX2NV

iTrader: (5)

Pretty much all these three are the same. They all give the engine more air to burn. Some are more efficient than others. SC needs the engine to turn the pulley. Turbo needs the exhaust pressure to turn the turbine. Nitrous needs nothing from the engine except it cost $$ to fill up. But all do the same thing, force more air into the engine.