DIY PROM Do It Yourself PROM chip burning help. No PROM begging. No PROMs for sale. No commercial exchange. Not a referral service.

VSS Speedo calibration

Thread Tools
 
Search this Thread
 
Old 12-07-2004, 03:14 PM
  #1  
Senior Member

Thread Starter
 
92BLKL98's Avatar
 
Join Date: Apr 2001
Location: Powder Springs, Georgia, USA
Posts: 794
Received 3 Likes on 3 Posts
Car: 1992 Black Z28 Hardtop
Axle/Gears: 2002 10 bolt w/3:23
VSS Speedo calibration

How do I figure VSS Ratio in the ECM Constants table in CATS Tuner? Can this be used to calibrate the speedo for rearend gear changes?
Old 12-07-2004, 03:16 PM
  #2  
Supreme Member

 
MrDude_1's Avatar
 
Join Date: Jun 2001
Location: Charleston, SC
Posts: 9,550
Likes: 0
Received 2 Likes on 2 Posts
Car: 91 Camaro Vert
Engine: 02 LS1, HX40
Transmission: 2002 LS1 M6
Re: VSS Speedo calibration

Originally posted by 92BLKL98
How do I figure VSS Ratio in the ECM Constants table in CATS Tuner? Can this be used to calibrate the speedo for rearend gear changes?
on a 3rdgen, the VSS is a set number of pulses per mile.

to calibrate for rear end changes, you swap plastic gears in the trans.. just like cable driven speedos.
Old 12-07-2004, 09:30 PM
  #3  
Member
 
Cliff92Z's Avatar
 
Join Date: Sep 2000
Location: Augusta, GA
Posts: 213
Likes: 0
Received 0 Likes on 0 Posts
Car: 1992 Z28
Engine: 350 TPI
Transmission: 700R4
Re: Re: VSS Speedo calibration

Originally posted by MrDude_1
on a 3rdgen, the VSS is a set number of pulses per mile.

to calibrate for rear end changes, you swap plastic gears in the trans.. just like cable driven speedos.
Or you can buy a unit that adjusts the pulses from Dakota Digital..
http://www.dakotadigital.com/Detail....-5/product.htm
Old 12-08-2004, 12:55 AM
  #4  
Supreme Member

iTrader: (1)
 
DENN_SHAH's Avatar
 
Join Date: May 2004
Location: houston
Posts: 2,262
Likes: 0
Received 0 Likes on 0 Posts
Car: 83 POS monte carlo 2015 chevy P/U
Engine: 92 5.7 tpi 5.3
Transmission: 700r4 6L60E
Axle/Gears: 2.42 too high
92BLKL98, the preferred way is what MrDude_1 said, you can also go with what Cliff92Z said, both will work.

i don't know about CATS, but with TunerPro RT with a 730 ECM running the AUJP bin with either 8d_v03 or Super_8dm2 ECU files, i know there you can make changes to alter the speed reading in the ECM.

the 8d_v03 ECU file is easier to set it with because it uses
0 - 255 for the setting where Super_8dm2 uses pulses per mile & when you change the pulse per mile enough the accept the
change, it changes by 1 number in 8d_v03.

as to how to calculate how much & which way to change it, i have no ideal, that would involve math & for me it was easier to run it on the dyno using real time emulation & my lap top.
Old 02-21-2005, 01:18 PM
  #5  
TGO Supporter/Moderator

iTrader: (12)
 
anesthes's Avatar
 
Join Date: Jul 1999
Location: SALEM, NH
Posts: 11,731
Likes: 0
Received 89 Likes on 75 Posts
Car: '88 Formula, '94 Corvette, '95 Bird
Engine: LC9, 355" LT1, LT1
Transmission: T5, Zf6, 4L60E
Axle/Gears: 3.42, Dana44 3.45, 3.23
Re: Re: VSS Speedo calibration

Originally posted by MrDude_1
on a 3rdgen, the VSS is a set number of pulses per mile.

to calibrate for rear end changes, you swap plastic gears in the trans.. just like cable driven speedos.
Why not just change the PPM, and speedo correction ?

-- Joe
Related Topics
Thread
Thread Starter
Forum
Replies
Last Post
InfernalVortex
Electronics
10
04-20-2021 11:31 AM
$750 L98
LTX and LSX
6
11-07-2015 02:26 PM
TMZIrocZ350
Engine/Drivetrain/Suspension Parts for Sale
1
10-07-2015 12:09 PM
rs_z28_vert
Engine/Drivetrain/Suspension Wanted
6
09-30-2015 09:47 PM
GTAman
Transmissions and Drivetrain
15
09-14-2015 09:53 AM



Quick Reply: VSS Speedo calibration



All times are GMT -5. The time now is 08:33 AM.