New Speedo cable frustration

[RockhillMtr 2.2L Find all posts View Profile Close RockhillMtr]

When I was doing all the metal work on my '70 years ago I had installed a new speedo cable since access to the tunnel from underneath was easy. I had a hell of a time routing it because it was too long. The only way I could route was to add an S curve in the footwell area where the cable exits the tunnel. It was not satisfactory but I didnt know what else to do. In retrospect I should have left the original one in there.

Anyway, of course, a few years later the cable broke I'm sure due to the poor routing.

So now Im once again doing tunnel work and got a new Gemo cable part number
901 741 111 01 and upon pulling the broken cable out and comparing the length, it is the same....too long. Far as I can tell I have the right part number for my car.

So what gives? If I install it I'm going to have the same issue no doubt. Anyone know the actual length of the original? Is there a different part number? Is the OEM Porsche cable a better length than the cheaper Gemo?

[Chris Pomares 2.4L Find all posts View Profile Close Chris Pomares]

I had the same issue. I took the piece that screws onto the speedo off and cut the cable housing shorter with my carbon blade dremmel tool. I inserted the cable measured for length and had two cables made.

[RockhillMtr 2.2L Find all posts View Profile Close RockhillMtr]

Chris what do you mean you had two cables made? How did you reattach the metal ferrule thats crimped onto the housing at the speedo end, to your shortened housing?
And how did you remake the square end on the inner cable after you shortened that?

[Chris Pomares 2.4L Find all posts View Profile Close Chris Pomares]

I carefully dremmeled thin slits 180 degrees off each other on the ferrule. Then I slipped a small hose clamp over the shortened housing. Then the ferrule and tightened the hose clamp over it. It’s never come loose in 8 to 10,000 miles. DeLuxe Speedometer here in Denver has the tools to make the square end that inserts in the speedo.
John Rullo
303-629-6958

[RockhillMtr 2.2L Find all posts View Profile Close RockhillMtr]

Gotcha. Ok thank you for the great info. I'm now calling around to try and find out if the original Porsche brand cable is the proper length. If so, I will probably go that route instead of modifying the Gemo one, but well see.

[moito tu felix austria Find all posts View Profile Close moito]

https://www.taflexa.de/

[RockhillMtr 2.2L Find all posts View Profile Close RockhillMtr]

Thank you for the replies. I contacted John up in Denver and he can do the shortening no problem. In the meantime, I've bought two NOS cables with the same part number to see how they compare to the new GEMO offering. I will report what I find.

[68S_SK2 2.0S Sportkit II Find all posts View Profile Close 68S_SK2]

I think, here you find the explanation for your problem:
Up to January 30th 1968 the speedo cable length was 2540mm, part no. 901 741 111 00
After that time the newer shorter 2440mm speedo cable was used, part no. 901 741 111 01.
Sorry, I only have the German service paper about that topic.

BR
Claudius

[RockhillMtr 2.2L Find all posts View Profile Close RockhillMtr]

Claudius, thats very interesting information. What I'm finding is that the original early cables, like what I found in my '70 are around 2440mm (about 96 inches), however all the current ones being sold are even longer than the 2540mm one the memo mentions.....at actually 2769mm (109 inches).

As an update to how I rectified this problem, I sent out my cable to John Rullo in Denver as Chris advised, and he shortened (and lubed) my NOS Gemo Made in Germany cable to 97 inches. You cant even tell that he did it, the ends are crimped exactly like the original. I routed the shortened cable through the tunnel the other day and connected it, 97 inches appears to be the perfect length with nice sweeping curves and no excess ridiculous routing like I had before. Money well spent, and I also took the opportunity to have him fix my broken odometer, have yet to test it but hopefully its working again.

[68S_SK2 2.0S Sportkit II Find all posts View Profile Close 68S_SK2]

Great, that you found a good solution for your problem.
BR
Claudius

[Uwon 2.0L Find all posts View Profile Close Uwon]

Claudius, thats very interesting information. What I'm finding is that the original early cables, like what I found in my '70 are around 2440mm (about 96 inches), however all the current ones being sold are even longer than the 2540mm one the memo mentions.....at actually 2769mm (109 inches).

As an update to how I rectified this problem, I sent out my cable to John Rullo in Denver as Chris advised, and he shortened (and lubed) my NOS Gemo Made in Germany cable to 97 inches. You cant even tell that he did it, the ends are crimped exactly like the original. I routed the shortened cable through the tunnel the other day and connected it, 97 inches appears to be the perfect length with nice sweeping curves and no excess ridiculous routing like I had before. Money well spent, and I also took the opportunity to have him fix my broken odometer, have yet to test it but hopefully it’s about to working again.

I’m about to instal my new cable so this thread is very appropriate. I’ll measure first thing tomorrow and will keep my fingers crossed overnight that we have “Short” cables here in Canada….(tongue-in-cheek).
My original cable just lay on the tunnel floor unattached to anything which I sure is not correct. Can somebody please describe to me the correct cable path and points to secure.
TIA
Johan

[Uwon 2.0L Find all posts View Profile Close Uwon]

Update. My new cable for my '71 from Porsche Canada measures 96". Good.

Anyone have any idea on the correct speedometer cable path through the tunnel?

Cheers,
Johan

[edmayo 2.0L Find all posts View Profile Close edmayo]

I think what I've done is use a plastic union from Lowes plumbing don't remember size, just take your cable with you and try the plastic plumbing unions until you find the fit. Then use that union to join the two cable ends and pull one in as you pull the old one out. I don't think there are any hold downs, just the cable routing under most of the heater cable tubes and clutch tube. You might need to remove shift housing and hand brake assembly for access. It used to be you could buy just the inner cable from Porsche and just push it through the old housing. Might be a way for a speedo shop to make something like that if you have the old inner.

[Uwon 2.0L Find all posts View Profile Close Uwon]

^^^Thank you edmayo. Unfortunately, I stripped everything out without taking any pics and then proceeded to embark on a bare metal restoration. I’m going to basically zipp tie it against the new brake line already installed which will keep it away from moving parts.
cheers,
Johan