My tach reads fine, about 800ish at idle and will hit 2600ish with stock settings. It's a cheap thing I had, all it says is supertach II and is on the 4-cylinder setting.

Only complaint is that the guage goes to 8 grand so i will never get to use the top half.

would the stock sensor on your truck need to be repositioned or respaced?

 

Ok, last dumb question and this should solve all my problems. I was planning on getting an Isspro Tach along with the Isspro wire harness for the Dodge CTD, but, the picture of the wire harness looks just like a bunch of wires with no kind of fuses or regulators or anything like that. Could I just save myself $40+ bucks and buy wires and make the harness myself?

Here is that wire harness...
http://www.isspro.com/proddetail.php?prod=R8912-92

Also, what tach would ya'll recommend?

 

I was thinking about checking that. We'll see.

 

I had a thought in the wee hours of the morning. Some where in my searching of the archives someone said that when they installed a dealer option tach in a pre-cranksensor 1st gen that they had to glue a (I'm translating that to 1) magnet to the crank pulley. Based on this, I wonder if the tach signal in the factory harness is a 1 pulse per rev signal. This would explain the approx. 1/2 rpm reading that seems to happen.

Perhaps a second magnet on the pully might make it work. Any thoughts??

 

My ISSPRO crank sensor uses two magnets.

 

That is good to know, I also have an old SUN supertachII,which I may put in now. The one that is in now is only 2 inches and is hard to see.That would also free a a place for a fuel pressure gauge.

 

so nobody else has a tach installed or has mounted one that works without having to put a second magnetic pickup on the crank?

 

I just installed a cheap Sun tack off of the mentioned 4 pin connector, I think the 4 cylinder setting is pretty close, on the mat, maxxed out it reads about 2900-3000. My engine also seems to idle high and the tach reads 8 or 9 hundred, it all seems about right to me.

X

 

I am going to install a isspro tach by using the isspro sensor kit with the two magnets. My dodge is a 92 with the computer but I think my computer is junk so I bought the complete kit and am going to install it. Anyone else ever done this? If so any help on installing would be a help. Still waiting on the sensor for now.

 

Yeah, I bought a new Isspro tach off ebay w/Isspro Dodge Ram harness(the aforementioned R8912-92) and simply plugged it straight in according to supplied directions(and verified by the ever-helpful sticky's here). It worked accurately from the get-go, but it was a diesel-specific tach(R-8503 I think?). The 92 crank to my understanding has only 1 notch for the sensor, so as you speculated with a tach set to 4cyl, an opposing magnet would be needed. Here is a link to Isspro's installation sheet that may help explain the sensor requirements/installation. Good luck! http://www.isspro.com/installation/IS236A.pdf

 

no i just installed a sunpro tach set to 4cyl that works just plugged into the factory harness. nothing else required. goes from a bout 750 in drive to 2700 in first gear to the floor

 

I finally got around to geting a picture of my tach as installed. I think it looks good. It still runs at about 1/2 speed but I will live with that until I have more time and the more important projects I have are taken care of.