tach reads to high after engine swap
Thread Starter
Junior Member
Joined: Sep 2007
Posts: 13
Likes: 0
From: P.E.I. Canada
Car: 92 rs camaro
Engine: 350 tbi
Transmission: 350 turbo with kit
tach reads to high after engine swap
Hi, I recently did a 3.1 conversion to 350tbi in a 92 rs and now my tach reads too high. I am wondering if there is a way to switch the tach to read 8 cylinder? I have to remove the cluster already to replace some bulbs. I am currently running an aftermarket tach but would still like to have the original reading correctly. Thanks for any info
Supreme Member
Joined: Jan 2006
Posts: 3,341
Likes: 10
From: Mooresville NC
Car: LOWERED ♦ CRIMSON METALFLAKE
Engine: ► 400 KUBES ◄
Transmission: 765R4
Axle/Gears: EATON POSI 4.56
Swap Shop
There is circuitry in the dash near the tach.
It’s contained on a small plug-in PCB or integrated in the main board.
On the PCB you’ll see a resistor chip.
Desolder pins 4 & 10.
Use a 500K potentiometer.
Solder it across traces 4 & 10.
Move the potentiometer to half way.
Start the engine and compare the tach reading with a test equipment quality tach.
Dial it in, unsolder the potentiometer, measure it and install a matching resistor.
◙◙◙◙◙◙◙◙◙◙◙◙◙◙◙
Happy Racing!
◙◙◙◙◙◙◙◙◙◙◙◙◙◙◙
Make Noise, Turn Left, Repeat
.
It’s contained on a small plug-in PCB or integrated in the main board.
On the PCB you’ll see a resistor chip.
Desolder pins 4 & 10.
Use a 500K potentiometer.
Solder it across traces 4 & 10.
Move the potentiometer to half way.
Start the engine and compare the tach reading with a test equipment quality tach.
Dial it in, unsolder the potentiometer, measure it and install a matching resistor.
◙◙◙◙◙◙◙◙◙◙◙◙◙◙◙
Happy Racing!
◙◙◙◙◙◙◙◙◙◙◙◙◙◙◙
Make Noise, Turn Left, Repeat
.
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theshackle
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Mar 5, 2017 06:37 PM





