LS1/6 (24x/1x) Engine Main Harness - Extended Length 558-133
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You have 30 days to request a return. All sale items are final sale.
Features:
- Plug and play with Dominator, HP, Terminator X and Terminator X Max ECU's
- Designed for use on 24x/1x LS engines
- Mount the ECU in a wide variety of locations such as on a roll bar or under the passenger seat
- 22" extended length
About Holley EFI

Find standalone EFI for LS, Coyote, Hemi and more at Holley.com. From engine swapping to managing up to 4000 horsepower, we have a solution for every project!
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