Engines and Components› Engines, Blocks and Components

Blox

Cylinder 4 Coolant Flow Upgrade Kit

$80.00

SKU: BXCC-50000-BLOX

Special Order
Special Order
Ships in 4–6 weeks
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$100 Minimum Order
30 Days Return
INSTALL DIFFICULTY
DIY PRO SHOP

Moderate — 2–4 hours

Overview

The Blox Racing Cylinder 4 Coolant Flow Upgrade Kit is designed for Subaru EJ20 and EJ25 engines. It addresses a known cooling design oversight in the left-hand cylinder head's #4 cylinder, which tends to run hotter due to insufficient coolant flow. This kit aims to increase coolant circulation to cylinder 4 by drawing flow from the water pump, thereby minimizing the risk of overheating and detonation.
Show original supplier description
The BLOX Racing Cylinder 4 Coolant Flow Upgrade Kit is engineered to enhance the cooling performance of Subaru EJ20 and EJ25 engines. Enthusiasts and tuners recognize that the factory design of the left-hand cylinder head can lead to higher temperatures in the #4 cylinder due to restricted coolant flow. This kit directly addresses this issue by increasing coolant circulation to this specific cylinder, drawing flow from the water pump. By improving coolant distribution, this upgrade kit helps to mitigate the risks associated with overheating and detonation, contributing to a more stable and reliable engine operation, especially under demanding conditions. Vehicle applications include the 2004-2020 Subaru STi, 2002-2014 Subaru WRX, 2005-2008 Subaru Forester XT, and 2004-2009 Subaru Legacy GT. Ensure compatibility with your specific vehicle year and model before purchase.

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

BrandBlox
Part NumberBXCC-50000-BLOX
CategoryEngines and Components
5,000+ Trusted brands
1M+ Enthusiasts
5M+ Parts sold
(760) 282-4645 hello@motormia.co

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Returns & Fitment

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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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