STI hardened (Group N) strut top mounts utilize a high durometer rubber compound to reduce suspension compliance and undampened motion. Also increases durability under harsh conditions such as gravel rally use.
Usually ships in 2 to 3 days.
What is the difference between this part and my original factory one? The rubber durometer (hardness) is noticeably increased. Otherwise it is identical to the original part.
What are the benefits of using this product? The compliance of the strut top mount is reduced. This minimizes undampened motion in the suspension and better resists geometry changes when subject to high cornering forces. Steering response will also be improved. Durability under extreme conditions is maximized.
Are there any downsides to using this product? The increased rubber hardness will transmit road imperfections more readily to the chassis. Higher NVH (noise, vibration, harshness) should be expected. However, it is generally still considered tolerable for daily driver applications.
This looks exactly like the part I removed from my car. Why? The Group N bushings and mounts are produced on the same factory line as the production parts and often use the same molds and will appear identical. However, testing the rubber durometer will show there is a difference. Additionally, usually (but not always) there will be some type of paint marking for identification. The Group N bushings will generally have different color marks.