Clamp on inductive tachometer

[SAXBY2]

I 've used the attached for conventional wired spark plug leads. Any suggestions on how to use it with the brass strip to #1 plug, or to another power lead to coil, etc ? It can be set for 4 or 8 cylinder powered by an internal 9 volt battery . The handle is squeezed to open the hole shown by the arrow.

 

[Jim Brierley]

You might try wrapping some tape around the brass plug lead and attaching it there.

 

[Jim/GA]

What would happen if you clamped it on the wire going from the coil down to the distributor cap? If you told it that the engine was a 4-cyl, I think the number reported would have to be divided by 4 (or maybe 2) to get the true RPM, but that's pretty easy to do in your head.

 

[alexiskai]

When I use the tachometer on my digital timing light, I use a piece of clear vinyl tube about 2" long. You cut a slit down the tube so that you can get it around the plug connector. The induction clamp holds onto the tube and doesn't touch the connector. Seems to work fine.

 

[SAXBY2]

Thank you all for the responses. I'll try the tape and tubing. Perhaps rubber thin wall tubing would work also.

 

[Klattu1929]

Ditto on response #4, I use a short piece of tygon tubing split lengthwise in a spiral. Put a small panduit on each end to hold it from moving. No problemo. Keep lead away from distributor as far as you can, on mine the rf will interfere with my readings.

 

[katy]

Get a spare spark plug brass strip, cover the center part with heat shrink, maybe 2 layers,
use that strip when checking engine RPM.

 

[SAXBY2]

Btw, what rpm do you guys like for full retard lever idle speed ?

 

[TomInCologne]

i have mine wound around the wire from coil to distributor, works great

 

[Big hammer]

Btw, what rpm do you guys like for full retard lever idle speed ?

450 + - 50 rpm any higher than 500 and then the GAV will come into use , lower than 400 has issues as well , Dave Renner had a post here about the idle

 

[Jim/GA]

i have mine wound around the wire from coil to distributor, works great

And then does it read high? Or can you change some settings to get it to read correctly?
.

 

[duke36]

450 + - 50 rpm any higher than 500 and then the GAV will come into use , lower than 400 has issues as well , Dave Renner had a post here about the idle

That's a good answer to a good ?. Wondered when the GAV kicked in

 

[TomInCologne]

And then does it read high? Or can you change some settings to get it to read correctly?
.

yes, you set it to 4 cylinders four stroke…

 

[RENNERS CORNER]

This unit is great, it has its own power source and it's a one wire clip hook up to the coil to distributor high tension lead wire.... super easy !

 

[TomInCologne]

i have one of these on my dash, 20,00 euros each, work great.
three or four revolutions around the wire between coil and distributor

 

[katy]

i have one of these on my dash, 20,00 euros each, work great.

Do you have a brand name or link?

 

[TomInCologne]

typical chinese ware, available with different brand names. they all look the same…

 

[Jim/GA]

Do you have a brand name or link?

Here is one that looks like Tom's:

https://www.amazon.com/dp/B0CJXKCFP9?tag=atomicindus08-20

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