Holley EFI Question

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Apr 10, 2020 | 11:41 AM

Bobby355

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Holley EFI Question

Hi,

I am planning an LS swap project but I don't know anything about EFI or tuning. I have heard really good things about all things Holley and LS, but I can't find the answer to this question anywhere. Does the Holley EFI system (i.e. Sniper / Dominator) replace the factory ECU? Or would I need the factory harness and tie the Holley EFI systems into it? I bought a 6.0 that has everything except the harness, so I need to know if I need to replace that or if the Holley systems could potentially replace it.

Thanks,
Bobby

Apr 10, 2020 | 11:46 AM

G Atsma

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From: Central Cal.

Look online. Holley's site tells you what is included. I think you get the harness, ECU, and sensors. Pretty much plug and play.

Apr 10, 2020 | 12:25 PM

jmm98LS1

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From: KS

You don't need the factory pcm or engine harness.

Apr 10, 2020 | 02:36 PM

QwkTrip

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What vehicle is the engine going into, Bobby? The answer to your question depends what the original ECM did and the system architecture that the vehicle was built with.

Apr 18, 2020 | 02:21 PM

Bobby355

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It's going into a 1971 Oldsmobile Cutlass

Apr 18, 2020 | 02:58 PM

EddieK

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I'm in the process of swapping a LQ9/4l80E into 1970 Cutlass, using Terminator X Max to control engine and transmission. Also using Holley mounts and oil pan. With Terminator you don't need factory harness or PCM.
Feel free to PM me if you have any questions.

Apr 29, 2020 | 09:38 PM

Ted Kay

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From: Greer, SC

Quote:

Originally Posted by Bobby355

You get the harness and PCM/ECU with the Holley Terminator X or X Max, depending if you need transmission or DBW. Sensors and injectors are not included, except for the internal MAP sesor in the PCM. Holley website has plenty of info and videos.