6V pos grnd 8 cyl tach

[Phil]

I want to hook up a small (2-3") tach to my 38 Packard. The major problem is that it's a 6 volt pos ground system - Can anybody help me out? [email protected]

[Monk]

Re: 6V pos grnd 8 cyl tach

Check this guy out..........I've been using him for several years
with great results.
Can probably answer your questions.

http://www.redlineg.com/index.htm

[TheSilverBuick]

Re: 6V pos grnd 8 cyl tach

What do the guys with 6volt VW's use? Then again I don't recall ever seeing a Tach in a VW.

[CTX-SLPR]

Re: 6V pos grnd 8 cyl tach

Weren't most Ford instraments 6V until the 1970s?

[fabricatordave]

Re: 6V pos grnd 8 cyl tach

Weren't most Ford instraments 6V until the 1970s?

THIS SHOULD BE IN THE TECH SECTION
actually 5 volt this is straight out ov mitchells on demand

instrument voltage regulator(IVR) is used in line with all bi metallic gauges except ammeter controls and maintains average pulsating voltage of 5 volts to each guage

they did this up till the late 80s but the tach still worked with 12 volts.

this was done on oil pressure water temp gas guage etc when IVR would go bad gauges would not reed right

just thought you would like to know

[CTX-SLPR]

Re: 6V pos grnd 8 cyl tach

Its not a question, its more of a suggestion.

[70.5CAMARO]

Re: 6V pos grnd 8 cyl tach

almost all gauges and sne sors work off of a 5 volt referance, you pull up and wiring diagram ( i use allldatapro online at work) and every sensor out there runs off of a 5 volt referance, to include the 4wd switchs, i/p and most airbag sensors. yah this should be in tech section.

[wrenchn2]

Re: 6V pos grnd 8 cyl tach

I think in the original post he was looking to buy one. But I got to thinking about this and does it make a difference with gauges if it is positive ground?

[70.5CAMARO]

Re: 6V pos grnd 8 cyl tach

it does make a differance with a tach, it will try to go backwards if you hook it up to a normal tach

[Huskinhano]

Re: 6V pos grnd 8 cyl tach

Simple, just electrically insulate the tach from the vehicle's ground. That way you can use the tach as designed without trying to figure out a complex solution.

[wrenchn2]

Re: 6V pos grnd 8 cyl tach

Thanks Husk I will remember that the next time I mess with one of those pos ground vehicles.