K-Series Transmission Performance Select Springs

Fits:

• 8th Gen Honda Civic Si
• 9th Gen Honda Civic Si
• 10th Gen Honda Accord
• 10th Gen Honda Type-R
• 11th Gen Honda Type-R
• 5th Gen Acura Integra Type-S

Honda officially calls these the "First-2nd Select Spring" and "Fifth-Sixth Select Spring." They are the parts in your transmission that are (partially) responsible for your shifter centering itself when in neutral.

By increasing the rate and preload of these springs, it's possible to realize a more decisive centering action for a sportier shift. ACUITY's K-Series Transmission Performance Spring Upgrade uses thicker wire and additional preload to provide a very satisfying, quick centering motion. This mod is particularly attractive because it provides such a noticeable change at a rather low price.