You cant get an SR installed for 3g’s so your comparing off numbers, if your comparing the v8 running in car price keep in mind thats the total cost for making 305hp, spending very little to make WAY more in the end will be cheaper.
How much are a set of injectors and a good ems and a tune going to run though? 3000 for the engine (providing you install it your self) plus what? I see it being cheaper long run to start with the most stock horse as you can, plus with the v8 theres power all the time not just when you go into boost.