It will derate boost and timing depending on octane. Run 93 for a few tanks and see if it returns to full power output.No mods are done I run 91 octane and I never heard any pops or anything but I just know when it left the dealer I was boosting at damn near 20 psi and I can’t get close now. Been super hot here lately but I don’t think that would cause 8 psi drop from heat but I am new to the turbo world also so not sure. Thanks everyone else actually giving me some advice or things to think about lol