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Quick Specs


If you’ve tried to get your tach to function after an LS swap, you know that it isn’t always a simple procedure. Save time, frustration and don't make a single cut in your factory wiring with AutoMeter’s Plug and Play LS Tach Harness. This Plug and Play solution lets you quickly and easily install the AutoMeter 9117 Tach Adapter onto your LS-derived engine. OEM spec connectors and wiring assure a hassle free installation that takes minutes rather than hours. No splicing, cutting or risks of voiding your vehicle's warranty. It’s completely reversible and couldn’t be easier. Get the best possible results in the least amount of time with the solution guaranteed to work right, the first time.
Feature Points
  • Includes AutoMeter 9117 tach adapter
  • The complete plug and play solution
  • Does not alter factory wiring
  • Plugs into factory ignition coil connectors
  • Sealed connector plug in to AutoMeter 9117 Tach Adapter
California Residents: Prop 65 WARNING prop65 Cancer, Birth Defects and Reproductive Harm


Rated 5 out of 5 by from Tach signal adapter As with most swaps that I have been involved with, the tach signal from the computer is corrupt and the signal is lost, with the plug and play set up that I ordered is the greatest thing (NO CUTTING AND SPICING) just unplug the coil pack for each bank and plug in the adapter harness and mounted the adapter on the firewall and run the tach wire to the tach,little square box on upper pass side firewall look close to see
Date published: 2018-06-18
Rated 5 out of 5 by from Super simple Exactly how it is advertised. Comes with everything. Plug and play all I had to do is solder one wire for my power safe nitrous gauge so it could read rpm for the widow switch feature. Also customer support was 10/10 straight to the point and knew exactly what I needed to get my system working and if anything else I had would interfere with it.
Date published: 2019-11-29
Rated 5 out of 5 by from Works perfect for gen 4 LS conversions Great conversion help for hen 4 LS engine when using older style tachometers
Date published: 2020-09-07
Rated 1 out of 5 by from #9123 didn't work for me I purchase a #9123 harness and adaptor to power my #2300 tech on a LS3 swap. It didn't help and I weasted a lot of money on it. It looked very impressive. A very easy harness to install.
Date published: 2019-07-26
Rated 5 out of 5 by from LS Tach Signal Adapter I reviewed the data involving clean LS1 ecm tach signals. The resistor fixes are a carnival of tricks that will burn more of your nerves than pulling that $170 from your wallet.
Date published: 2020-04-12
Rated 5 out of 5 by from Easy fix It is very easy to install and worked with no changes needed on the gauge.
Date published: 2020-03-01
Rated 5 out of 5 by from Tach Easy to install. Nice simple connections. Works perfect
Date published: 2020-07-18
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hello i have a 1975 GMH kingswood and the original tachometer gauge connects to a conventional coil on the negative terminal. i am doing and LS1 conversion and enquiring if your plug & play tach adaptor kit 9123 will work with the original tachometer

Asked by: beaver
For these types of motor swaps we recommend giving our technical support a call to verify if this indeed will work for you application. There are some LS motors that do not need the tach adapter and will become an unnecessary purchase. Please give us a call at 866-248-6356 for further assistance.
Answered by: Steve from AutoMeter
Date published: 2024-01-11

Hi - I'm putting a 2009 mustang 4.6L in a old fairlane - and want to use one of your oldschool tachs bolted to the dash - will the 9117 tach adapter work for this Ford? the product shows it's for an LS engine is why I ask.

Asked by: joelFairlane
The 9123 setup is specific to LS applications. The 9117 will work with the Ford 4.6 motor.
Answered by: Jim from AutoMeter
Date published: 2023-02-17

What Harness can i use to use the factory 4 guage cluster in the console of my 68 RS Camaro, the guage cluster has Battery, Temp, Fuel, and Oil Pressure guages? Im doing an Ls swap.

Asked by: kenp
Thank you for your question. Please give our tech support team a call at 866.248.6357 so we can fully understand your project and recommend the correct parts.
Answered by: Alex at AutoMeter
Date published: 2023-01-27

Hello. I have a client with a 69 Firebird that has a GMPP LS3 crate engine with an OER hood tach. The LS3 tach signal is 1/2 actual RPM. Would this device correct that?

Asked by: Mike C
This product is not designed to drive an OEM tach. It will only work correctly with our tachometers.
Answered by: Jim from AutoMeter
Date published: 2023-01-24

i install that kit on my 2004 ls swap engine in my foxbody and i have issu with needle bouncing up and down.... what i have to do with that???? you guys as suggest install a resistor between 2 wire and its correct the problem couple minute AND BACK AFTER

Asked by: MAXime
Could you send an email to our tech team or give us a call?
Answered by: Thomas From AutoMeter
Date published: 2023-01-23

i have a 2003 5.3 ls engine in a2002 jeep wrangler that had 4.0 liter 6 cylinder.will this operate the factory tach and if so do you know what wire i should hook it to?

Asked by: andy 17756
We do not have definitive data on this working with factory tachs. This is built to work on Autometer tachometers.
Answered by: Thomas From AutoMeter
Date published: 2022-11-30

I have a 2010 camaro 6.2 v8. I have a factory tach which works fine but I would also like to install your 5"auto meter shift light tach. Will AUTO METER 9123 adaptor work on my car?

Asked by: Biggrigg74
The 9123 plug and play adapter an harness will work on your car.
Answered by: Jim from AutoMeter
Date published: 2022-10-13

Hi, I have a 68 Camaro with the tic tic tach and a LS3 crate motor and was wondering if this would work with the combo I have.

Asked by: Ron364e
The 9123 should be plug and play for your application.
Answered by: Jim from AutoMeter
Date published: 2022-07-08
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