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Exhaust› Headers, Manifolds and Components

Doug Thorley

Tri-Y Header, 4:2:1 Design

$1,199.96 $985.00 Save $214.96

SKU: THY-509Y-C

In Stock
In Stock
Ships by Sep 12
Free Shipping over $200
$100 Minimum Order
30 Days Return
INSTALL DIFFICULTY
DIY PRO SHOP

Moderate — 2–4 hours

Overview

The Doug Thorley THY-509Y-C is a Tri-Y header designed for 2005-2019 Toyota 2.7L Tacoma, 4Runner, Prado, and Hilux models. It features a 4:2:1 header style, constructed from steel with a silver ceramic coating.
Show original supplier description
The Doug Thorley THY-509Y-C Tri-Y header is engineered to enhance the performance of your Toyota 2.7L engine found in 2005-2019 Tacoma, 4Runner, Prado, and Hilux models. This header utilizes a 4:2:1 Tri-Y design, which is known for increasing power across the widest possible RPM band, making it an ideal upgrade for street performance. Constructed from durable steel, the header features a silver ceramic coating for enhanced heat resistance and longevity. The primary tube diameter is 1-1/2 inches with a 14-gauge thickness. It includes 2-bolt flange collector attachment, a 3/8-inch flange thickness, and comes with necessary bolts and/or studs. Gaskets are not included; factory gaskets should be reused. This kit does not include a Y-pipe.

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

BrandDoug Thorley
Part NumberTHY-509Y-C
CategoryExhaust

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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.

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.

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