This has always been a touchy subject when it comes to Stock Block Subaru cars making power. The question is frequently asked, "How much power can my Stock engine Subaru WRX or STI handle"? That question has so many variables as to how long an engine will last.
At the end of the day If you are looking to reliably make power a built engine will 9 times out of 10 take more abuse and last longer. however, you can make stock blocks last a good chunk of time when cared for and done properly. But just remember a stock block is always one bad knock event away from dying.
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