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Subaru OEM STI Short Block Subaru STI 2018 Type RA / 2019

$2,703.13

SKU: S00N 10103AD020

In Stock
In Stock
Ships by Jun 11
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Non-Returnable Item
INSTALL DIFFICULTY
DIY PRO SHOP

Professional / shop required

Description

The Subaru OEM 2.5L Shortblock (MPN: 10103AD020) is designed for the 2018 Subaru STI Type RA and 2021 Subaru STI. The block uses the '705' casting, and the crankshaft is a nitrided, full-counterweight design. The Type RA pistons are machined cast pistons from Hitachi with a thicker crown and increased wrist pin support, weighing 424 grams. The connecting rods are identical to the GR STI's rods.

Fitment

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Specifications

BrandSubaru
Part NumberS00N 10103AD020

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Buy with Confidence

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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