I've finally gotten the tachometer on my 1997 960 to work with the 5.0, and it turns out it's really pretty easy, if you have the Dakota Digital Universal Tachometer Signal Interface SGI-8 $79.95

http://www.dakotadigital.com/index.cfm/page/ptype=product/product_id=127/category_id=287/home_id=59/mode=prod/prd127.htm

Its just a little box that converts the 5.0 negative coil tachometer signal to work with the 960's tachometer.

I mounted the SGI-8 in the glove box just because that's where I have the 5.0 EEC-IV and it's close to where I ran the wires thru the firewall.

You will need to run a switched 12 volt and ground to the SGI-8, as well as a wire to the negative side of the coil.

I got a wiring diagram for my 1997 and determined that the tachometer input is the red & white wire that runs from the computer module in the drivers foot box up to the instrument cluster. You can access the wire by removing the plastic cover under the steering column. Find the red & white wire in the bundle, cut it, and extend it to the SGI-8.

Setup and configuration is pretty easy, just set the dip switches for a 8 cylinder engine and a 4 cylinder tachometer. Apparently Volvo only made one tachometer for both the 4 cylinder and 6 cylinder engines and adjusted the signal in the computer.

That's all I did, and it works great!

http://img.photobucket.com/albums/v378/67Cobra/Volvo/PC080148b.jpg

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