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read with interest your remarks concerning limiting rpm's on your '47 clipper...I have been wanting to have a RPM readout capability on my 48 custom8 club sedan but cannot locate a 6V tach....I'm assuming you've had success with a 12V tach ?? pardon my ignorance but how would that be hooked-up ? My '48 has a 4.06 rear end but with overdrive it reverts to a 2.92....at 70mph in overdrive my test tach shows 2300 rpm's...I would like to know what my engine is doing all the time...thanks

6 volt tachs are still around. Several make them. Here is one company which has several different ranges listed under 6v gauges. If you use their search box on the site for 6 volt tachometer, an entire page of them comes up.westach.com/ I don't know the company but they mention use in classic cars and seem to have been around a long time. Maybe someone here has used their products.

Thanks Howard....Westach had 5 or 6 suitable tachs at 3500rpms....hate to show my ignorance but some have different ranges (1 1/2 to 3 imp/rev) what does that represent ? does it matter...all seem to be pos. or neg. ground...?

On the tech info page, go to applications guide, 6 volt section and it will give some choices for products and then once tachometer is selected, engines. You can select a tach model and go to the instructions page. Some schematics for several models are available. You can check to see if there is one for a model you like.

Here is a cut & paste of sections taken from a schematic they show as typical for an 8 cylinder -- 4 imp. The wiring is simple -- 2 wires, one to points and one to ground.

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there is a devise called Tiny Tach - it's a digital read out cost about $50

That Tiny Tach is not a bad little unit. Inductive coupling and battery operated so no voltage worries. Only downside is the modern look (if that's important) and battery can't be replaced. Guess if the battery lasts the claimed 5 years, not much worry there.

Thanks again to Howard and Phil...I have a lot to work on, greatly appreciated...Dick

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I am taking a guess here, but believe the imp/rev means the number of impulses per revolution. A tach with 3 imp/rev would be for a 6-cylinder engine and one with 4 imp/rev would be for one with 8-cylinders. This guessing is based on four cycle engines fire all the cylinders in two revolutions of the crankshaft regardless of the number of cylinders. The tachs I am familiar with have three wires: Battery, distributor, and ground. Some have a fourth for an instrument light.

(o[]o)

That is a lovely-looking 2255! Almost certainly the rarest of the Custom 8 body styles. If you haven't given them to me before, I'd love to have the VN, Briggs #, thief-proof number, and engine # if original to the car. PM them if you want to keep them confidential.

HH56: I purchased the Westach 2CT34-6V 4imp/rev. and installed as directed....tested vehicle at 70 mph and dial showed 2800 rpms..I was disappointed as my previous test with an older Sundeen tach had shown 2300 rpms...I used all the formulas for computing RPM - Gear Ratio- MPH with known tire diameter...all showed that the rpms at 70 mph with 29" tire dia, to be 2368 rpms...which I find reasonable...How do I account for the misreading on the Westach (2800rpms)??? I purchased the one rated at 3500 rpms...the Custom8 is rated at 3600rpms...should I have purchased a 5000rpm indicator....I can't see how that would help...am I on the right track ???? when I computed the rpms at 2800, I found that the gear ratio would be 3:44 but the manual says its 2:92 in overdrive...can the Westach be adjusted, perhaps thats a question reserved for the Company...Dick