Analog tach for VW

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TiPi

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The one I had specified a fuse. The tach should already have a very high internal resistance.
doesn't protect the ignition from a short through the wire. The resistor at the P-lead connection is to safeguard aganist any short incl the wire.
 

Dana

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doesn't protect the ignition from a short through the wire. The resistor at the P-lead connection is to safeguard aganist any short incl the wire.
If the fuse is up front at the magneto (as mine was), it protects everything downstream just as a resistor would.

The unfused P-lead going back to the magneto switch is just as susceptible to a short.
 

TiPi

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that fuse is a "make you feel good" device! the current is very low and extremely intermittent (very brief at the ignition time), so for a fuse to work it would have to be extremely fast and rated very close to the current in the P-lead.
Unfortunately, you can't protect the P-lead to the kill switch or you won't be able to switch off the ignition. Double-insulated wiring and good quality switch & connections are all you can do. It is more likely that the original P-lead fails in open circuit.
 
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PixiePilot

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Yes, in Colorado you won't see my 29 inches, normal asperation. Manifold pressure gage surely demonstrates density altitude pressure drop...about one inch per 1000 ft of climb. Thanks for the fuse info.
 

n45bm

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Westach makes one that will fit but depending on your limit it might be in the “break the bank” area for you.

Here’s the one I think you would need *ouch*

Prices for this kind of stuff is sky rocketing! Shazam!
 

Pops

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When I was building the SSSC, I ordered the 2AT32 Westach from AS. Recieved a 2 cycle 6K tack. Called and was told to ship it back and they would send the correct tach. The other one came in the mail before I got the first one shipped. They shipped me the same wrong tach the second time. Now I had 2 wrong tachs. This time I called AS and told then that I was shipping both wrong tachs back and canceled the order and bought a Tiny-Tach somewhere else.
 
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