Please help with changing speedo gears
#1
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Please help with changing speedo gears
I just got in my new 145mph cluster with the white faced guages. I'm going to pull out my 85mph cluster, but while I'm at it I'd like to correct my speedo (I changed from 3.23 rear gears to 3.70). I read the FAQ about this but I still have a couple questions.
It mentions Drive and Driven gears in the FAQ. Are these both behind the speedometer, or am I going to have to deal with gears in the transmission?
Also, would anyone happen to know what gears come in an 87 IROC that originally came with an 85mph speedometer, a 5-spd, and a 3.23 rear end?
Any help would be greatly appreciated, I really can't wait to bolt these in!
It mentions Drive and Driven gears in the FAQ. Are these both behind the speedometer, or am I going to have to deal with gears in the transmission?
Also, would anyone happen to know what gears come in an 87 IROC that originally came with an 85mph speedometer, a 5-spd, and a 3.23 rear end?
Any help would be greatly appreciated, I really can't wait to bolt these in!
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You might want to ask this over in the transmission forum - or wait a bit and the moderators will probably move it for ya...
I've never done it so I can't help you out other than to suggest you try over on the other board.![](https://www.thirdgen.org/messgboard/smile.gif)
Steve
I've never done it so I can't help you out other than to suggest you try over on the other board.
![](https://www.thirdgen.org/messgboard/smile.gif)
Steve
#3
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yeah this isn't the place for this post. the boards were seperated the way they are to maxamize peoples area of expertise. any way the drive gear is the one on the out put shaft inside the trans and the drien gears in the one on the speedo cable.
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ICON Motorsports
1st & 3rd
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ICON Motorsports
1st & 3rd
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Car: 4
Engine: 6
Transmission: 5
The speedo will slap right in. If you look closely, you will notice that the distance from 0 to 60 is exactly the same on the 2 speedos, the one can just go farther before it hits its stop.
The 3.23 came with a 7-tooth blue drive gear (probably what's already there) and a 18-tooth white driven one. You'll need a 18-tooth one for the 3.70s. Like ede said the drive gear is on the trans tailshaft and requires major disassembly to change; the driven on is in a little housing which plugs into the side of the trans just in front of the driveshaft. It takes longer to jack up the car than it does to swap the gear. One 10mm-head bolt is all you have to deal with.
Somebody on this board is looking for the 3.23 speedo gears...
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"So many Mustangs, so little time..."
[This message has been edited by RB83L69 (edited December 26, 2000).]
The 3.23 came with a 7-tooth blue drive gear (probably what's already there) and a 18-tooth white driven one. You'll need a 18-tooth one for the 3.70s. Like ede said the drive gear is on the trans tailshaft and requires major disassembly to change; the driven on is in a little housing which plugs into the side of the trans just in front of the driveshaft. It takes longer to jack up the car than it does to swap the gear. One 10mm-head bolt is all you have to deal with.
Somebody on this board is looking for the 3.23 speedo gears...
------------------
"So many Mustangs, so little time..."
[This message has been edited by RB83L69 (edited December 26, 2000).]
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