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GM LS 24x Plug and Play Engine Harness-1st Gen
GM LS 24x Plug and Play Engine Harness-1st Gen
EV1 versus EV6 versus Multec Fuel Injector Connectors
MS3Pro EVO with GM LS 24x Plug and Play Harness
GM LS 24x Plug and Play Engine Harness-1st Gen
GM LS 24x Plug and Play Engine Harness-1st Gen
GM LS 24x Plug and Play Engine Harness-1st Gen

GM LS 24x Plug and Play Engine Harness-1st Gen

From: $799.00

Product Quantity

Alternator Lead Extension


4L60E CAN Transmission Control


4L80E CAN Transmission Control


Out of stock


Designed for MS3Pro 1st Gen plug and play installation.  HARNESS ONLY in this listing.

The MS3-Pro 24x LS Plug and Play Harness is the highest quality, best value option for LS Motors in the industry today.  Save your hard earned time and money while experiencing the virtually limitless feature set of MS3-Pro Engine Management System.  Simply choose your injector style from the drop down menu!

This harness is set up for MS3Pro 1st Gen ECU ONLY.

The MS3-Pro LSX Series plug and play harness is professionally engineered and easy to install.  Fire up your engine on day one!   All wiring is composed of TechFlex woven, self-extinguishing wrapped hi-temp TXL & GXL automotive grade wire with OEM Delphi & TE connectors. Reach the battery under the hood or in the trunk with 4 gauge power & 10 gauge ground wires.  All relays and fusing live in a single, waterproof fusebox and the fuel pump wiring / relays / fusing is big enough for pumps that can handle 1000whp or more right out of the box (10ga wire, 30amp circuit).  Additionally, all of the available I/O of the MS3-Pro are brought out in the harness to make expansion as easy as possible regardless of the featureset you’re planning to use, allowing for killer features like traction control, bump box, table switching, flex fuel, and more.  This harness was designed with room to grow!  And did we mention it’s show-quality-drop-dead-gorgeous?

This harness also is designed for optional automatic transmission control using the AMP EFI transmission controller (sold separately).  Literally just plug in our transmission controller using the proper sub-harness (for 4L60E or 4L80E) and you’re ready to control your trans!

Required connections:
Constant Power
Constant Ground
Switched Power
Alternator light

Suggested extra connections:
Fuel Pump Power
Tachometer Signal

Note that the alternator connection is designed for high mount alternators such as Corvette and truck setups. Low mount alternator setups such as Camaro, Firebird, CTS-V, and GTO accessory brackets, as well as other aftermarket accessory drives that do not have the alternator high on the driver’s side, require our alternator extension cable.

*All parts are sold for OFF ROAD RACE-ONLY, ground-vehicle use only. Aftermarket EFI/EMS systems are not for sale or use on pollution controlled vehicles. Alteration of emission related components constitutes tampering under the US EPA guidelines and can lead to substantial fines and penalties. Your state/district may also have specific rules restricting your tampering with your vehicle’s emissions system. In short, as stated before, our official policy has to be RACE or OFFROAD USE-ONLY in ground based vehicles ONLY.

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What size screws do I need for the fuse box mounting?

  • It uses #10-32 mounting screws.

Does this harness have the MS3-Pro controlling the alternator?

  • No. You will need to wire the alternator to the charge lamp. That will activate the alternator. See details in the manual.

Questions & Answers

    do you have a harness for electronic throttle ls6?
  1. 0 votes
    Q do you have a harness for electronic throttle ls6?
    Asked by mike b

    We currently do not have a production ready device to control the electronic throttle, so our harnesses are set up for cable operated throttle only. A cable operated throttle is a pretty easy swap for these motors though.

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