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LeesTruk · 10-12-2023, 05:31 AM

If you use an aftermarket tach, you can usually set them to 4, 6, or 8 cylinders. The PCM puts out a 4 cyl. signal, so set the tach to 4 cyl. or have your tuner set the PCM to 8 cylinder signal. Either way, you're gonna need to add a pull-up resistor to the white signal wire (usually 1K to 5K resistence of at least 1/2 watt), as well as boost the signal with a 12v switched source.

10-12-2023, 05:31 AM	#4
LeesTruk Registered User Join Date: Mar 2015 Location: Manchester, CT Posts: 429	Re: Tach wire If you use an aftermarket tach, you can usually set them to 4, 6, or 8 cylinders. The PCM puts out a 4 cyl. signal, so set the tach to 4 cyl. or have your tuner set the PCM to 8 cylinder signal. Either way, you're gonna need to add a pull-up resistor to the white signal wire (usually 1K to 5K resistence of at least 1/2 watt), as well as boost the signal with a 12v switched source.