Help! how to wire a stock tach to v6 2.8

[paddlerdan]

I have an '86 XJ W/2.8 V6, I am upgrading my gauges to include a stock tach. I need help on wiring a stock tach from a 91 HO 4.0 I6 to a stock 86 2.8 v6 that had no tach.
This engine has a normal GM type external coil.
Details would be very helpful ie: wire colors, etc. Do I need the harness plug(s) from the donor xj?
Will trying to hook up different wires to see what works wreck anything?
Thanks.

PS: Yeah the v6 sucks and all that, but I gotta live with it for now.

 

[muddshutter]

PM 5-90. He is your ONLY hope.

I would suggest getting an external - bellhousing setup for a 4.0, sending it to him and making him feel guilty. Then he'll help you out.

 

[paddlerdan]

Thanks Muddshutter I pmed him.
Any other info out there???

 

[99xjstl]

Why not just mount a aftermarket tach, that way you have to run just one wire from the coil and be done?

 

[dirkg]

This was probably one of the easiest things I did to my XJ. I had an 84 but I would think 86 is the same. The wiring harness is all there for all the gauges. I just got a whole instrument panel from a wrecker and screwed it in place. I got the tach, the better gas guage, real temp and oil guages instead of lights, and I think that was it. Screwed it in and everything worked, except the tach. I had pulled one from a 6cyl and I had a 4cyl. So the tach read very low. I pulled a new one and put it in and everything worked. But then my XJ went from having over 300k miles to only just over 130k.

 

[paddlerdan]

Thanks dirkg! Now that I hear that I feel confident enough to drop the bucks on the used gauge set. Any problems with the gas gauge? Are the sending units compatable?. 86 xj - mech. fuel pump. 91xj electric fuel pump. Just a thought. I know they (the fuel pumps) are separate from the sending unit but who knows?

Dan.

 

[RichP]

Another option is to get a tach from JC Whitney, I've seen a hood mount one like the firebirds and GTO's used.