Changing Odometer

[kuehjo]

Yeah - I know - that sounds bad. But that's not at all my intent.

I have an '81 928. Pretty car, clean. But the speedo unit only goes to 85mph (WTF???)

So I'm looking at changing out the instrument cluster - or at least the speedo unit. So my questions are these...

1.) Can I just exchange instrument clusters, or is there a sending unit that needs to be exchanged as well to accommodate the 165mph cluster as opposed to the 85 mph cluster?

2.) Can the odometer be exchanged separately so that I can maintain the original mileage reading on the car?

3.) Is there a certain year range that will exchange directly? Will a late 80's speedo unit fit into an early 80's car? Does THAT require a different sending unit

I have ZERO desire to screw with the mileage and set it back - I simply want the car to be as reasonably accurate/original as possible - with the exception of a better speedometer!!!

[Danglerb]

Almost all odometers have had a drive gear fail at some point, or will have, so the gear that fails should be replaced anytime serious work on the cluster is done. Part of the job is setting the mileage as you reassemble the odometer. Various 928 vendors sell a good replacement gear for about $28, and its not a very tough job. Around $100 I think if you send it out, but not a lot of shops will replace the bad gear with aftermarket, putting in an original gear that should fail like the first one.

Speedo difference is some resistor I think and a new face, pretty sure all the speedo units are the same, maybe even between other models of Porsche, but best to check part numbers at a few vendors.

Clusters are different, half a dozen or so types.

Speedo and Odo pretty sure are a single unit.

All the sending units I think are the same, tachs are different, but more differences than just those between clusters in different model years. Not sure on just the speedo, as I said above, check the part numbers.