Subaru Six Cylinder Harnesses

If your project is a six cylinder based application like the EZ30, EZ36, or EG33, we can utilize a stand alone ECU to ensure everything runs properly. We build the ECU to the main connectors on the stock engine harness from scratch and merge it into your chassis harness for a simple, clean, plug and play harness with all factory functions working just like our 4 cylinder harness merges. 

All of our Harnesses are Quality Checked before being shipped and are covered by our Lifetime Warranty. Click here for full warranty

You Give Us

The bulkhead harness (harness behind the dash) from the chassis you plan to swap the six cylinder engine into. 

We build the ECU to main plugs coming off the 6 cylinder engine with new wire, connectors, and sleeving. Let us know any additional features you would like to add in like Flex Fuel, Oil Pressure Gauge, Boost Controller etc. Then we merge our fresh engine harness into the factory bulkhead harness from the chassis that you provide.

What We Build

All You Do

When you receive your harness, plug everything back in and get your car tuned to program the stand alone ECU. 

Have a question about your build? Looking for custom work? Want to know more about pricing for your project?

Contact Us! 


$1199 - Brand new harness from Haltech ECU to main plugs coming off six cylinder engine

$800 - Merge to donor bulkhead harness for a plug and play wiring kit

$1947 - Haltech Elite 2500 ECU

$299 - Wideband 02 Sensor

$60 - Approximate cost for return shipping

Total Pricing - $4,300

*Typical price breakdown for a EZ30r or EZ36R with drive by wire and AVCS. EG33 and EZ30D would be same labor but could utilize Elite 1500 or Elite 2000 Haltech ECU.

Why do we use a Haltech Elite ECU?


We understand that this not the cheapest ECU on the market, but it is better to buy one ECU that will handle everything you need than to purchase a second ECU later down the road and have to rewire and retune everything.  We utilize the Haltech Elite series because it has enough inputs and outputs for the project and potential updates. It has the most user-friendly interface we have seen so if you end up changing settings you will really appreciate it. Add-ons like a wideband and digital dash are just a matter of plugging them in. The Elite has tons of support, not only from Haltech, but most tuners utilize it so no matter where you are you can get support.

Turn Around Time


Standard turnaround time is subject to change based on the volume of rush fees, but 4-6 weeks can be expected for non rushed orders. Please let us know your project time frame and we will do our best to work with you.​

Things to consider for a 6 Cylinder Swap

  • 6 cylinder swap will not pass emissions or BAR due to the Standalone ECU

  • An inexpensive engine does not mean an inexpensive build. Many pieces will need to be custom fabricated or modified since there is little to no aftermarket parts for six cylinder swaps yet. 

  • Check out our blog post here for more thing to consider. 

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iWire is here to simplify your Subaru powered project, big or small. Focus on the mechanical aspects and we'll take care of the wiring headaches for you.

Lake Forest, CA





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