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Old 12-23-2024, 08:08 PM   #1
AcampoDave
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Location: central California
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Bouncy lagging tach

Pretty much like the title says. It bounces up incrementally as I wind up the motor. It also reads low most of the time. I've swapped the tach (Autometer) with another identical version. I've swapped the coil, I've tried a different ground. Tomorrow I'm going to swap the trigger wire to the HEI and I'm wondering what guage wire I should use for that as well as the 12V hot. I think it's all wired with 18 guage now. I can't think of anything left to try besides that, but if anyone has a suggestion please let me know. Thanks.... oh and I'm sure the tach itself is set for 8 cylinders too.
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Old Yesterday, 10:11 PM   #2
Willshook
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Re: Bouncy lagging tach

Is the HEI getting a clean, direct 12V?

Does it steady if you turn on the headlights?
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Old Today, 10:53 AM   #3
raggedjim
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Re: Bouncy lagging tach

Maybe this would help?

https://www.youtube.com/watch?v=-6j3glUtecY
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