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Old 05-16-2022, 03:56 PM   #1
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Join Date: Mar 2015
Location: Washington State
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Holley Terminator Max X & Electronic Speedo

So I just installed the Holley Terminator Max X. The system install was very simple. The interesting thing I found with this was that there is no "stock" setup for a Speedo. Stock meaning programed into the system when you get it. I am running full Autometer Gauges, Tach and Speedo specifically. With that said, the stock tach wire from the Holley system is for a "full" V8 tach system. With my past PSI LS Wiring harness, I had to set up the Tach as a V4 setup, in my case it is dip switches smaller than HB lead, lol. So I had to switch it to V8, that worked perfect. Now for the speedo... there is a setting that you need to setup in the software. Make it somewhat short, i get into the software, found the I/O (Inputs & Outputs) and found the 4 wires on the J1 connector. Output 1 & 2 to Electric Fan, 3 & 4 to IAC system and AC Shutdown with IAC as an Input. So I selected the AC Shutdown (Pin G) and moved it to the Un-Assigned area and then moved from this area the "Speedo" to where the AC Shutdown was. Then found the area in the software for the AC and found the AC Shutdown selection and un-selected it. Save this file to a name I Picked, Save that file to the SD Card located in the handheld unit and downloaded that file to the ECU and tada, that speedo works!
Yes I could have just done this on from the laptop, but I like to have the handheld in view at all times.
I will have a custom tune done by Andrew (he came highly recommended by others on LS Site) and will do it online, this is a new experience for me but looks to be cool.
Just wanted to pass on my experience with the system so far. So far, I really like the system!!
John 3:16 - Saved me... God Bless
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Old 10-23-2022, 08:31 AM   #2
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Join Date: Oct 2022
Location: Raleigh, NC
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Re: Holley Terminator Max X & Electronic Speedo

Hey Sir, can I call you? Iím trying to do the same thing with autometer gauges
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Old 03-28-2023, 05:59 PM   #3
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Location: Broken Arrow, OK
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Re: Holley Terminator Max X & Electronic Speedo

In case anybody else does this there is one issue you can have with this setup depending on the brand of gauges. My Speedhut gauge requires a 1-100 volt pulse between 1000 to 250,000 ppm. The Holley software allows changing the pulses, though the factory default is 4000 pulses per mile. The problem lies in the fact that the Holley ecu supplies a ground pulse rather than a positive pulse. My gauge couldnít find the proper signal so could not calibrate. I had to tap into an auxiliary 12v wire and splice in a resistor to the signal wire in order for my speedo to read any speed. This was shown as optional wiring in my Speedhut instruction sheet but there was no explanation as to why it was optional. But it worked and hopefully someone someday can use this information on their Holley Terminator X build.
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Old 03-28-2023, 09:19 PM   #4
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Re: Holley Terminator Max X & Electronic Speedo

Just fyi. I haven't used the Holley stuff but there is guy over on that does remote tuning for the Holley stuff. His name is Andrew. Gets great reviews.
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