Tach help after the swap

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Feb 11, 2015 | 07:04 PM

Zee man

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Joined: May 2014

Posts: 56

Tach help after the swap

A while ago I swapped a 98 ls1 into my 94 z 28. The factory Tach doesn't read correctly, it looks to be @ 50% or so. I know this is a common problem with swaps, is there a fix for it?
I believe my tach is only seeing .5 of the ignition pulses. Not real sure about how to proceed. Any help is appreciated.

Feb 12, 2015 | 07:07 AM

Injuneer

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Joined: Nov 1998

Posts: 71,097

From: Hell was full so they sent me to NJ

Re: Tach help after the swap

Mismatch between the LT1 PCM tach output signal and the LS1 PCM tach output signal. I believe this ("tach signal") can be changed in the LS1 PCM with HP Tuners.