Need help with tachometer
 

I have a 74 tach and I was told that there is a separate piece (transducer?) that is located in the rear to the left of the engine.

I need this piece. The newer tachs (74plus) have this piece inside the tach.

I am trying to get the tach to work with a 3.6 Motor. other suggestions?

Your old tach requires a high voltage signal from the coil and not from the DME
output. I don't remember ever seeing a tranducer on any early car. Just connect
the tach wire (purple/black) to coil side which goes to the ignition unit.

NO, no, no ... none of the 2.4 or 2.7 tachs required the ballast-resistor assembly mounted on the relay/fuse/regulator panel! It was phased out during 2.2 engine production.

As far as the 2.4/2.7 tachs go, some will work with the DME output, and some won't ... it is a matter of sensitivity. The Voltage 'swing' of a DME signal is not quite as great as the solid-ground signal from points ... and the 100 Ohm pullup resistor to +14 Volts.

Give the tach a try hooked directly up to the DME signal ... it won't hurt the tach, and it might work fine!

My 74 tach worked just fine with the 3.6 until I swapped everything for 964/993 gauges. Just give it a try. I am sure it'll work just fine.

http://forums.pelicanparts.com/uploa...1074576346.jpg

Ingo

I did try it briefly before I discovered my engine was crap and needed rebuilding, and it did not work.

When I sold the previous engine I gave the new owner everything on the panel next to the engine. So when the tach would not work I started to wonder if I gave away something I needed.

I also had some strange issues with the alternator light, When the key was in the off position the light stayed on. So I will be chasing this down too.

I did talk to Patrick Motorsports today, in their conversion harness they put a voltage amp to raise the signal out of the DME for the earlier tachs so I need to check this to make sure there is no issues with the soldier connections.

An IRF9630 or IRFD9123 HEXFET buffer ought to do the trick ...

Sorry about my "english" guys !!!

Taco-Tachmeter- or what ever you call it, please try it in my langvitch: "turteller"

Thanks for all the advises !!!