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[ic932]

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Its a 944S gearbox with the electronic speedo sensor removed and a 931 speedo cable attached instead.

Good news if you want to fit 951 hubs/spindles an brembo's AND want to get rid of the snailshell to fit a 944S2/951 tranny?

Obviously, the cable will not be long enough but how easy would it be to attach two cables together?

Would the callibration even be correct?

Any thoughts guys?

[Smoothie]

[ic932]

Good thinking Smoothie, that makes sense.

[RC]

Like Smoothie said, you need an exact 1:1 ratio with the axle shafts and run a tyre with the same OD as OE spec.

Failing that you can get some mechanical speedos recalibrated. Have had them changed at an instrument shop (that was also a VDO agent) when changing diff ratios or gearboxes. There are also many different types of little gearboxes available, some with various teeth gears to alter the drive ratio. May also be a convenient way to couple 2 cables together. Quick google on "speedometer gearbox" gives many options, including UK based ones.

http://www.transmissioncenter.net/speedometer_calibration_______va.htm

http://www.importedvehicles.co.uk/cable_driven_speedos.htm

[bruce76-924]

Great idea but I'm pretty sure that the 944 spedo drive runs at twice wheel speed, so some form of recalibration will be needed. Could you join the cables together via some kind of gear set up to reduce the speed - just the sort of project a model enginner would love!!

Good luck, Bruce.
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1976 924 LHD, full cage, semi tube chassis, 951 brakes, lightweight 951 body panels.
1.8t engine conversion with Holset turbo and 6 speed Audi gearbox.

[bruce76-924]

Sorry RC, just seen that you suggested joing cables with gears!!!
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1976 924 LHD, full cage, semi tube chassis, 951 brakes, lightweight 951 body panels.
1.8t engine conversion with Holset turbo and 6 speed Audi gearbox.

[RC]

No worries Bruce.

Personally have no idea at what ratio the cable rotates. No argument here if you say 2X. Didn`t think it would be that simple somehow?

Recall getting a little reduction box that fitted on the back of the speedo between the cable when doing a MPH to Km/H conversion to get an import through rego. So was just a suggestion.

[Buwani 931]

I used to make these where I worked.



You would be better off making an all new cable, putting the ratio box where you want it. A good shop will have a mile ( or whatever you call them there ) meter to figure out what ratio you need. Hook up meter to your cable-drive a marked mile-get reading-make correct box.

Shawn
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1980 931
That's thirty minutes away. I'll be there in ten.

[ic932]

Great input guys.

This was just an after-thought really. I was taking pics to show a fellow board member the differences between the snailshell gearbox set-up and the Audi set-up.

Knowing that the 924 speedo cable fits perfectly into the electronic speedo fitting and that the cable is long enough to move the problem to the centre-console area inside the car is a good start.

It will be simple enough for me to attach the cable to a 924 speedohead then drive an observe...Once i get the motor/trans back in of course lol!

[flosho]

Does VDO make "oem" looking speedometer except in electric?
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[This Space For Rent]

[ic932]

[Joes924Racer]

Speedo cables for my 79 its just a one piece that goes to the front hub..
though i do know that some of the later cables are 2 piece yup one long cable and a short one the short one runs off the guage and goes into a littl;e black box up under the dash and the long one runs out to the hub.
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1979 porsche 924 Na
1980 porsche Turbo 931GT Replica
Have u ever driven a turbo.

[morghen]

There are companies that can make a custom cable for this applications...i'm sure of it.
Joining two cables does not sound such a good ideea to me but fab-ing a new one and using this method does !
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Supercharger and EFI kits
https://www.the924.com