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Eddie914
The tach on my 914/6 (conversion) has lost it's dampening. The tach needle is nice and steady as long as the engine rpm is constant. When the rpm changes quickly (such as when gear changes are made), the needle bounces. It takes a fews seconds to settle.

I remember reading a thread about adding a resistor to the circuitry to repair the problem.

Even though a 3.2 six has been installed in the teener the engine electronics and induction are still "old school" ... 40mm Weber carbs and points, condenser & CDI ignition. The tach is an early 70's 911 model with a 7,200 rpm redline.

Can anyone help me out/

Thanks

Eddie
detoxcowboy
http://nhspeedometer.com/914/1.htm

North Hollywood Speedo installs them.. did mine and it works perfectly
underthetire
I remember that too. It was a capacitor though,not a resistor. I can't find it anymore either.
underthetire
Now I remember, the resistor was kind of a fake out to run V8's and use the stock tach. The bouncing problem was a dried up I think 1UF capacitor inside the tach. Thats bouncing during RPM changes. Bouncing tach all the time was points/or alternator/or VR going bad.
dr914@autoatlanta.com
If it has lost it suddenly but worked before it may just be dirty contact points. However Palo Alto has added ballest to tachs that we have had converted without having to find the very expensive three blade capacitor installed on the factory six relay boards.

QUOTE(Eddie914 @ Jun 17 2010, 11:36 AM) *

The tach on my 914/6 (conversion) has lost it's dampening. The tach needle is nice and steady as long as the engine rpm is constant. When the rpm changes quickly (such as when gear changes are made), the needle bounces. It takes a fews seconds to settle.

I remember reading a thread about adding a resistor to the circuitry to repair the problem.

Even though a 3.2 six has been installed in the teener the engine electronics and induction are still "old school" ... 40mm Weber carbs and points, condenser & CDI ignition. The tach is an early 70's 911 model with a 7,200 rpm redline.

Can anyone help me out/

Thanks

Eddie

Michael N
I think this is the link. Bouncing Tachometer Link I soldered in a capacitor and it dampened my old tach about a year ago. At first I went too much dampening and the tach was too slow to respond to the revs. I then changed to a different capacitor and the tach is now perfect. Spokes photo in post #7 helped a bunch.
Eddie914
Thank you everyone!

You are the best!

Eddie
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