how about using an inline speedo calibrator to gear down a mech tach? Im talking about the ones used in big trucks to change the ratio from the tranny to the speedo. I have one sitting on the shelf that reverses the rotation of the cable. Very interesting bit. Wouldnt that work for the reverse sweep tachs?
How would that work? Speedo shows the RPM (measured in a linear distance) of the driveline after the transmission changes the output speed. Tach shows the RPM before the transmission changes it. The two are only the same at a gear ratio of 1:1 (high gear), with a manual trans.
Anyone hear of a Jet-Tach? It is a V8 8000 RPM sweep Tachometer with a green and red wire..it definitely looks 60's vintage.
Also have these, told they both in perfect working order. Are these rare? value if working good? both are in good physical shape, no peeling or pitting, do they both need senders? I am assuming yes? I appreciate any info. thanks 811892 sending unit
I just purchased a 1939 Chevy 1.5 ton truck that has a working SW cable driven tachometer... Any information regarding the model or year of manufacture would be great. I also would like to find out where I can send it out to have the face restored... Thank you.
Dragging up this old post. Just recently picked up this tach and can’t find any info on it. I have a mechanical SW in my pickup so thought I would use the older one but cable is different. I got really lucky on the drive @ $50 cdn from a flathead guru on Vancouver Island.
I wasn't aware of this thread when I was all over this stuff in January. I wasn't aware of the distributor-cap cable-drive adaptor. Has anyone got a pic of one? It seems like something which could be 3D-printed, maybe? That'd make a 3:1 version possible, for my converted speedometer idea.
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