Speedometer For Getrag 5-speed

[opelgtboy70]

The 5 speed is in. I replaced the speedo gear with the one from opel gt source. Why do I have to use a different speedometer? Will it work with the 5 speed and just be off in the mph's?

Karl
70 GT

[wolf32]

Who said you have to use a different speedometer

[opelgtboy70]

Opel GT source said I have to change to a different year speedo.
Speedo # 1062

[opelgtworld]

Speedometer drive gear
Number of teeth:
red 18
yellow 19
blue 20

Which you need, depends from the speedometer, the transmission,the rear axle and also on your wheels.


Tacho-Berechnung und Endgeschwindigkeiten - Rüdiger Cordes

[markandson]

With out the proper speedo you will not get accurate MPH reading. The gearing inside the speedometer must be different from the suggested one to the one you have in your car.

[soybean]

Karl, Here is a single post about after the swap.
Here is a thread. Check post nos.9.
Hth, Jarrell

[Crazy Harry]

Karl,

The speedo will work, but the MPH will be off if the components don't match and the from my experience the difference is significant between a W=897 and a W=1062. If the speedo reads the wrong MPH then the odometer will be off too!

It would be best to match the speedo with the proper transmission take-off. According to "opelgtworld" you may get away with changing the speedo take-off gear at the transmission rather than changing the gauge in the dash. The speedo converts the speedo cable rpm to the gauge readings. Changing the take-off gear at the transmission matches the speedo cable rpm to the gauge head calibration. I haven't tried changing the speedo or the transmission gear so I couldn't tell you which is easier, but I'm guessing the transmission end might be the way to go if you can get the right color gear.

The link "opelgtworld" gave is good, but remember you need all the right info and those calculations are metric, km/h. The conversion for the W number is mentioned in the fine print, about 1.6 km/mile. For a W=1062 in MPH the W you would use in the link is 660, the table shows the conversion between MPH and km W numbers.

Sorry for the rambling reply, hope it helps.

"opelgtworld": Viele Dank für den Link! Thanks for the link!

Regards,

Harold.

[jerseydave]

Karl

I have an extra W-1062 speedometer I just got a few weeks ago off of ebay.
Price was good and wanted to have a back up! Let me know if your interested.

[opelgtboy70]

OPGTS sent me the correct tranny gear (plastic piece). They also told me to switch to the 1062 speedo. I was wondering why I have to switch both.

Karl
70 GT

[baz]

so they match

[GTJIM]

Here is a link to the math:

http://www.opelgt.com/forums/1e-othe...eedometer.html