Sale

Engines and Components› Engines, Blocks and Components

Darton

Dry Sleeve Set for Subaru EJ25 WRX STi

$683.48 $491.96 Save $191.52

SKU: DAR300-031-3D

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

Advanced — 4+ hours

Overview

The Darton DAR300-031-3D is a set of four dry sleeves designed for the Subaru EJ25 WRX and STi engines. These sleeves replace the factory cylinder liners with a stronger, more durable surface capable of handling increased power. As dry sleeves, they do not feature coolant passages in the top flange, providing a more rigid structure to prevent warping and expansion.

Darton cylinder sleeves require finishing and honing by a machine shop to match the specifications of the pistons being used. They are compatible with bore sizes ranging from 99.5mm to 102mm.
Show original supplier description
The Darton DAR300-031-3D is a set of four dry sleeves engineered for Subaru EJ25 WRX and STi engines, offering a robust solution for enhanced engine durability and power handling. The 'Dry Sleeve' design eliminates coolant passages in the top flange, resulting in a more rigid structure that resists warping and sleeve expansion, crucial for high-performance applications. Constructed from centrifugally cast nodular iron, Darton sleeves are known for their exceptional strength and durability. The unique casting process ensures a tough bore finish that promotes a quick and complete piston ring seal for optimal combustion. The product specifications include a bore of 3.890 inches, an OD of 4.250 inches, and a wall thickness of 0.180 inches, with a flange thickness of 0.500 inches and a flange diameter of 4.600 inches. The application range for these sleeves is for EJ25 engines with bores from 99.5mm to 102mm. It is critical to note that Darton cylinder sleeves must be professionally finished and honed at a machine shop to precisely match the specifications of the pistons being installed. This ensures proper fitment and performance. The sleeves are sold as a set of four. This product is specifically designed for the following vehicles: 2006-2014 Subaru WRX EJ25 and 2004-2020 Subaru STi EJ25.

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

Fitment Guaranteed

Don’t gamble
on fit.

Log your build in the MOTORMIA app and we’ll guarantee this part fits your exact setup — or your money back, return shipping covered.

Available on iOS & Android

Specifications

BrandDarton
Part NumberDAR300-031-3D
CategoryEngines and Components
5,000+ Trusted brands
1M+ Enthusiasts
5M+ Parts sold
(760) 282-4645 hello@motormia.co

Buy with Confidence

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.

View Full Return Policy

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.

Free shipping over $200 in the continental US. Alaska, Hawaii, U.S. territories (Puerto Rico, U.S. Virgin Islands, Guam, American Samoa, and the Northern Mariana Islands), and international orders carry surcharges — most appear at checkout. Some exceptions (LTL freight, or suppliers who quote freight only after we place the order) won’t. In those cases we’ll reach out with the exact charge before your order moves forward.

View Full Shipping Policy