I suppose this is very overdue, but...speedometer calibration
#1
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Car: 91 Firebird, white
Engine: L03 :(
Transmission: 700R4
Axle/Gears: 4th gen, 3.23
I suppose this is very overdue, but...speedometer calibration
This is waaaay overdue but I think it's about time I tackle this issue
First of all my car is a 1991 base model Firebird with an L03 and 700R4.
Back in December I did a rear end swap on my car...my car came with a 2.73 open rear end and I put in a 3.23 posi rear end...since then my speedo has (understandably) been off roughly 10mph (higher or lower depending on how fast I am going), because of the gear change.
My question is...I'd like to re-adjust my speedometer to compensate for the gear change... how can I do this?
I've heard from some places that I'll need new speedo gears inside the transmission...from others I've heard it's as simple as a computer adjustment.
HELP! Thanks...
First of all my car is a 1991 base model Firebird with an L03 and 700R4.
Back in December I did a rear end swap on my car...my car came with a 2.73 open rear end and I put in a 3.23 posi rear end...since then my speedo has (understandably) been off roughly 10mph (higher or lower depending on how fast I am going), because of the gear change.
My question is...I'd like to re-adjust my speedometer to compensate for the gear change... how can I do this?
I've heard from some places that I'll need new speedo gears inside the transmission...from others I've heard it's as simple as a computer adjustment.
HELP! Thanks...
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Car: 91 Camaro RS
Engine: 5.0L TBI (ebl inside)
Transmission: T-5
Axle/Gears: 3.42 lsd 10 bolt
You need atleast one new speedo gear if not two. I'll run the calculations later when I have more time.
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Car: 1991 Chevy Camaro
Engine: 305 TBI
Transmission: 700R4
Axle/Gears: 3.42
Yes, all you have to do is replace the speedometer gear(s). They are located on the tailshaft of the transmission and on the VSS itself. Here's a step-by-step on how to replace them:
http://sethirdgen.org/vss.htm
Once you know what gears you need, just check out the FAQs on the main page for the GM part number list for the different gears. When you remove the extension housing to replace the gears, you should replace the 2 seals on it. The front o-ring seal, GM part number 1358899, and the extension housing oil seal, GM part number 8673526. If you want/need a new speedometer gear clip, it's GM part number 6261781.
http://sethirdgen.org/vss.htm
Once you know what gears you need, just check out the FAQs on the main page for the GM part number list for the different gears. When you remove the extension housing to replace the gears, you should replace the 2 seals on it. The front o-ring seal, GM part number 1358899, and the extension housing oil seal, GM part number 8673526. If you want/need a new speedometer gear clip, it's GM part number 6261781.
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Car: 91 Firebird, white
Engine: L03 :(
Transmission: 700R4
Axle/Gears: 4th gen, 3.23
Originally posted by TJfive0
Jungleman, where did you get your posi rear end from?
Jungleman, where did you get your posi rear end from?
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