Many people focus on power, suspension or tires trying to find that extra bit of time or grip or whatever it is they are looking for. But somehow people overlook the addition of a quality differential. Over the last year this is something that I wished I would have upgraded years ago. When I added my OS Giken front and rear differentials to my STI I didn’t realize the value they would then add without the issues that so many other differentials bring to the table.

Here is a comparison of the OS Giken rear differential vs the stock STI differential. OS Giken will tune the differentials to your liking prior to shipping them to you which is unlike other manufacturers. This really helps quicken the installation process. OS Giken offers a Front and Rear differential set for the STI. Continue reading →