There is a Renntech pulley mod available for a slight bump in hp/tq. Check down the board for posts. The trans is also an AMG reinforced/upgraded driver-adaptive unit and pretty much bulletproof. The SRT track experience guys told me the only component that may be prone to failure is the differential but only after really, really hard abuse. They also said the front discs could use an upgrade to cross-drilled ones as the stock discs have a tendency to overheat and warp under extreme (track) abuse.