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Gen III HEMI Harness with TPS and Idle Air Control Connections. This wiring harness interfaces a Holley EFI ECU to a Gen III HEMI engine with an aftermarket cable actuated throttle body. It is meant to be used in conjunction with an injector harne...

Gen III HEMI Harness with TPS and Idle Air Control Connections.This wiring harness interfaces a Holley EFI ECU to a Gen III HEMI engine with an aftermarket cable actuated throttle body. It is meant to be used in conjunction with an injector harnes...

An Injector Harness is required and Holley offers two. The harness with USCAR/Stock injector connectors will cover most applications that are using the factory injectors. The other harness is for the Bosch and Holley (or Jetronic/Minitimer) inject...

An Injector Harness is required and Holley offers two. The harness with USCAR/Stock injector connectors will cover most applications that are using the factory injectors. The other harness is for the Bosch and Holley (or Jetronic/Minitimer) inject...

GM 4L60/80E Transmission Harness - Complete terminated harness with j4 connector to operate GM electronic transmissions.For 2009+ GM 4L60/80E Transmission use Holley EFI Part Number 558-455.Specs: Brand: Holley EFI Category: Air and Fuel Deliver...

An EFI system depends heavily on being supplied a clean and constant voltage source. The grounds of an electrical system are just as important as the power side. Our Holley EFI Harness Kit comes complete with the main harness, power harness and in...

Upgrade your 2.8L Duramax Canyon or Colorado with this Flo-Pro 3" turbo-back exhaust system. Built for competition use, this system delivers maximum flow by replacing your restrictive OEM exhaust with a high-performance aluminized steel design. En...

Bring back the boost your Duramax was built to make. If your turbo is showing signs of wear—slow spool, inconsistent power, or oil-related issues—this direct-fit replacement restores strong, predictable performance. Built for work-truck duty and d...

Reduce soot. Simplify your engine bay. Support long-term reliability. This EGR Delete Kit is engineered for 2016–2022 Chevrolet Colorado and GMC Canyon trucks equipped with the 2.8L LWN Duramax engine. Designed for off-road and competition applica...

Eliminate EGR system issues, increase efficiency, and extend your Duramax’s engine life. Vehicle Compatibility 2006 GMC Sierra 2500/3500 6.6L Duramax LBZ 2007 GMC Sierra 2500/3500 6.6L Duramax LBZ 2006 Chevrolet Silverado 2500/3500 6.6L Duramax L...

Serious clamping strength for serious Duramax builds. This Gator Heavy-Duty Head Stud Kit is designed to reinforce the cylinder head sealing system on 6.6L Duramax engines from 2001–2016. Whether your truck tows heavy, runs aggressive tuning, or s...

Introduction Protect exposed wiring after emissions modifications with the Duramax DPF Delete Plug Kit (2011-2023). Designed for GM/Chevy 6.6L LML, LGH, L5P and L5D engines, this kit seals unused exhaust and EGR connectors to block out moisture, ...

Hold the boost. Protect the power. Upgrade your 2004.5–2005 LLY Duramax with a reinforced silicone intercooler hose kit built to handle heat, boost pressure, and long-term engine demands. Whether your truck is stock, tuned, towing heavy loads, or ...

Upgrade your GMC Sierra or Chevrolet Silverado 2500/3500 with this comprehensive All-in-One Duramax LML tuner and DPF delete kit, designed for 2011–2016 6.6L Duramax diesel engines. Engineered for maximum power, reliability, and efficiency, this ...

Free up exhaust flow and support off-road performance. This 4” Stainless DPF Delete Pipe is built for 2011–2015 Chevrolet Silverado and GMC Sierra 2500/3500HD trucks equipped with the 6.6L Duramax. Designed for competition and off-road application...

Free up exhaust flow and support performance-focused builds. This 4” Stainless Steel DPF Delete Race Pipe is engineered for 2015.5–2016 GMC Sierra and Chevy Silverado 2500/3500HD trucks equipped with the 6.6L Duramax and OEM-style 3-bolt turbo fla...

Vehicle Fitment: This Cold Air Intake is compatible with 2007.5, 2008, 2009, and 2010 GMC Sierra and Chevrolet Silverado 2500/3500 models equipped with the 6.6L Duramax LMM engine. Please note, this product ships directly from the manufacturer. Sh...

Vehicle Fitment This Duramax 6.6L Cold Air Intake Pipe is custom designed for the following models : 2011-2016 GMC Sierra 2500/3500 2011-2016 Chevrolet Silverado 2500/3500 It fits only vehicles with the OEM-style 3-bolt flange on the turbo direc...

Upgrade your 6.6L Duramax with this 3" stainless steel downpipe, designed to outperform the restrictive factory unit. With a 20% increase in exhaust flow, this downpipe reduces EGTs, improves turbo spool, and boosts efficiency—whether you’re towin...

Upgrade your 2004.5–2010 Chevrolet Silverado or GMC Sierra 2500/3500HD 6.6L Duramax with this 3" stainless steel downpipe. Built for durability and performance, this downpipe improves exhaust flow by 20% over stock, lowers engine bay temperatures ...

Maximize exhaust flow, lower EGTs, and unlock real performance from your early Duramax. This 4" or 5" Downpipe-Back Race Exhaust System is built for 2001–2007 Chevrolet Silverado and GMC Sierra 2500HD/3500HD trucks equipped with the 6.6L Duramax e...

Increase exhaust flow and unlock stronger performance with a stainless race exhaust built for the Duramax LML. This Downpipe-Back Race Exhaust System is designed for 2011–2015 Chevrolet Silverado and GMC Sierra 2500HD/3500HD trucks equipped with t...

Unlock your truck’s full capability with the EFILive AutoCal V3 DPF Delete Tuner, complete with Black Bandit custom tuning. Built for GM Duramax 6.6L engines, this tuner delivers horsepower gains, improved fuel economy, and real-time control, ens...

The Duramax LML EGR Delete Kit is a proven upgrade for 2011–2014 GMC Sierra, Chevrolet Silverado 2500/3500, and Savana/Express Vans. This kit completely removes the restrictive factory EGR system, helping to improve performance, reliability, and e...