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Ksport

Slimline 6-Piston 350mm Big Brake Kit

$3,303.30 $2,852.85 Save $450.45

SKU: BKSB220-342SO

Special Order
Free Shipping over $200
$100 Minimum Order
Non-Returnable Item
INSTALL DIFFICULTY
DIY PRO SHOP

Moderate — 2–4 hours

Overview

The Ksport Slimline Big Brake Kit is a performance braking system designed for the 2015-2018 Subaru WRX STI. This kit features a 6-piston caliper and 350mm (13.8") slotted, vented, 2-piece rotors with cast iron construction and an aluminum center for reduced rotational mass. The Slimline caliper design allows for compatibility with most factory wheels or wheels with limited clearance, addressing a common issue with aftermarket big brake kits.
Show original supplier description
The Ksport Slimline Big Brake Kit offers enhanced braking performance for the 2015-2018 Subaru WRX STI, specifically engineered to address the fitment challenges posed by aggressive wheel fitments and limited caliper clearance. Its"Slimline" caliper design draws inspiration from OEM single-side piston caliper thickness, enabling compatibility with many factory wheels where larger aftermarket calipers would not fit. This kit includes forged aluminum 6-piston calipers paired with 350mm (13.8") 2-piece slotted and vented cast iron rotors. The 2-piece rotor construction, featuring an aluminum center hat, helps reduce rotational mass, improves braking response, and minimizes the risk of rotor warpage by allowing for more unrestricted expansion and contraction. The larger brake pad surface area compared to OEM pads significantly enhances overall braking performance, while the street-compound pads are suitable for performance driving. The kit also incorporates stainless steel brake lines, which resist expansion under high temperatures and pressures, leading to a firmer pedal feel and faster pedal response. The minimum wheel diameter required for this kit is 457mm (18").

Product descriptions are provided by our supplier partners and may not always be perfectly accurate. Not sure this fits? or call (760) 282-4645 and we’ll verify before you order.

Fitment

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Specifications

BrandKsport
Part NumberBKSB220-342SO
CategoryBrakes
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Returns & Fitment

Built for enthusiasts. Every order is backed by our 30 day return window on eligible items. Unused and uninstalled products may be returned with approved RMA and no restocking fees when received in new condition. Orders placed through the MOTORMIA app with a complete build qualify for our Fitment Guarantee — free return shipping if the part doesn’t fit your exact setup. The guarantee covers fit only; installation must follow manufacturer instructions, and we recommend a qualified shop for parts marked Difficulty 4–5.

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Shipping

Orders are processed in 1–3 business days. In stock parts ship promptly from our partner network. Special-order items either aren’t currently stocked or are built to your spec — expect 4–6 weeks. If a part goes on backorder while your order is in the queue, we’ll reach out and work through discounted alternatives together.

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