Originally Posted by LiLpNoY
I've been reading up on how the injectors being Maxed out? Would it be a good idea to upgrade those before going for a protune? Currently stage two using the ots Cobb tune. I do want to protune but just thinking what to do so I'm not paying for every little part.
The best way to tell is by logging injector duty cycle %. Run the car up to redline in 3rd or 2nd and see how high a % you hit. I like to keep it below 90% at redline. The COBB AP should be able to log injector duty cycle. There is a second or even third fuel table your tune will switch to in case of a heavy knock event, its around a 10% or more increase in fuel. You should always maintain this in case of an issue.
Injectors need to be upgraded anytime you increase air flow much beyond stock levels with the Subarus. This might be from more boost, bigger turbo, intake changes, cams, etc. I find that the STI is good to about 18-20PSI on the stock turbo with min mods before you really should size up the injectors.
Due to the fact our octane is low up here we tend to have to run rich which means more fuel then others run. COBB OTS tunes have you covered with a very rich tune typically, good and bad.