So I was just dreaming about upgrading my diff the other day, and then I saw an FRS and I thought to myself, I wonder how those differentials hold up... After doing a bit of research, they aren't super strong or anything but they're stronger than our diffs, that's the conclusion I've come to at least. Anyways even though this wouldn't something I would do in the near future but there's a possibility if I get this new job that I'll have some money and nothing to do with it. This obviously wouldn't be an easy task but I just wanted to put it out there for you all to think about. Anyways let me know if there's any similarities or if it's impossible or just any thoughts feel free to post it. Thanks

 

Previous BRZ owner here, the gearing blows.

 

Spend your extra money on something worth doing, or maybe find a new hobby? People upgrade the diffs on this car, but are done with options that are an actual improvement with minimal effort and cost. The Ford 8.8 and R200 are the most common. The ap2 diff will take more abuse then an ap1 due to the upgraded carrier bearing end caps, which are the initial weakest link causing 99% of the failures you hear about. But even then, its becuase they are driven hard without much consideration.

 

Or just get a puddymod diff. It will bolt right in, and be way stronger than stock. Unless you are doing a mega 500+ HP build, no need to go to Ford 8.8 extremes.