Tach pulses per revolution - LS1TECH

Go Back   LS1TECH > LS1-LS2-LS3-LS6-LS7 PERFORMANCE > Conversions & Hybrids
Log In 

Conversions & Hybrids
LSX Engines in Non-LSX Vehicles
Sponsored by
Don Hardy Race Cars

Tach pulses per revolution

Thread Tools Search this Thread
Old 01-13-2006, 04:27 PM   #1
Conversion master
iTrader: ( 1 )
Trader Rating: 1
Join Date: Dec 2001
Location: Gig Harbor, Wa
Posts: 861
Default Tach pulses per revolution

How many tach pulses come from the PCM per revolution. I think it is 2? Is it a 5V squarewave signal?
Fuel Injected 1970 Corvette
LS1 and Six speed
C5 brakes
conversion site

2004 Silverado SS
Black and Dropped.
SS Pics
70 LS1 is offline   Reply With Quote
Old 01-13-2006, 04:39 PM   #2
sawzall wielding director
iTrader: ( 4 )
G-Body's Avatar
Trader Rating: 4
Join Date: Sep 2004
Location: Downers Grove, IL
Posts: 3,071

Yes, the computer puts out 2 pulses per revolution (4cyl output). I am not sure what style signal it is but you can convert it to 4 PPR (standard 8cyl output) by using EFI live 7 or HP Tuners.
85 El Camino SS black and silver, factory buckets. 6.0L/4l60E 3.73 posi. Down for rebuild
2005 CTS-V Stock...for now daily driver
1985 Monte Carlo SS 5.3L/4l80e/turbo still in pieces.
Originally Posted by Rodder
"possible" is a relative term around here... anything is possible. It's "possible" to put a whole K3500 4x4 dually truck rolling chassis under a brand new Mini body. Is it reasonable? No. Does it make sense? No. Is it possible? Yes.
G-Body is offline   Reply With Quote
Old 01-14-2006, 08:38 AM   #3
Teching In
Trader Rating: 0
Join Date: Jun 2005
Posts: 9

Hey jeff,
I donít know if you remember me consulting you on tach problems on my vette. Any way itís an 81. I rebuilt the tach and hooked it directly to the signal from the PCM It works but I suspect that it off a bit. Iím very happy that the tachometer moves again. I just need to get my hands on a programmer and check if the PCM is set on 4 or 8 cyl and play with it.
zamika0a is offline   Reply With Quote

Similar Threads
Thread Thread Starter Forum Replies Last Post
Need Help Setting Parameters for Speedo bshyster65 PCM Diagnostics & Tuning 10 09-23-2015 03:53 AM
I need to flash my Corvette ECM to make it think its an FBODY...help please The Plastic Lizard Conversions & Hybrids 6 06-07-2015 11:22 AM
T5 to LC9, VSS? superman22x Manual Transmission 2 11-13-2014 09:14 AM
Any way to make a v6 tach work on v8 output? MaxxAction Conversions & Hybrids 6 07-11-2014 07:53 AM
TR6060 VSS gear tooth count /vss pulse output 67firebirdak Manual Transmission 1 05-20-2014 07:21 AM

53, conversion, converting, corvette, cpu, impulses, ls1, output, pulse, pulses, rev, revolution, revolutions, setting, steps, tach, tachometer, tachometers

Thread Tools Search this Thread
Search this Thread:

Advanced Search

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are On
Refbacks are Off


All times are GMT -5. The time now is 11:46 PM.