I have an '85 4 cylinder car with the 85 MPH speedo. There is an '87 6 cylinder car with the 120 MPH speeometer in the junkyard. Would it plug & play?

Yes, but you will want the whole cluster because they are backlit, and then you will lose your Oil pressure gauge unless you can get the rally gauges too.

^^^^^^^^^ what they said lol


Yes it is plug and play. You will lose your oil pressure gauge though unless you add the rally gauges or keep your current tach but then the lighting will be different as the 120mph are backlit and the 85mph is not. But its a worth while upgrade. I did this to my 85gt and my 87 base

[This message has been edited by Spoilt_87fiero (edited 11-19-2010).]

I was going to just swap out the speedometers, not the whole cluster. Does that mean it won't be illuminated at night?

Try it and let us know how it works out. I, for one, and curious.
If your car was a V6 SE, it would have a back-lit 85 MPH speedo, and the swap of just the speedo would work fine.

quote Originally posted by Mike Gonzalez: Yes, but you will want the whole cluster because they are backlit, and then you will lose your Oil pressure gauge unless you can get the rally gauges too.

How can you add the rally cluster to a car that didn't come with it? Does it have the wiring already there behind the console? If I just swap the speedo, won't it look strange since the colors and font on the numbers won't match the other gauges?

Do yourself a favorand just do the whole cluster. All you need to do is switch tach-boards (two screws) and plug it in. Easy-peesy. If you do the whole cluster, it wont look strange at all.. it will look BETTER.
After that, you can also add on the aux gauges which also match and get a voltage meter to boot.

[This message has been edited by tbone42 (edited 12-05-2010).]

84's didnt have the rally gauges... so there is no wiring for it...

Here is a link if you want to add rally gauges to a 84 or 85.

http://www.frontiernet.net/...tt/AuxGageInstal.htm

Jack

I scored these at the junkyard from an '86.



What do you mean by swapping the tach board?

nice score !

You can uscrew the board off the back of one tach and put it on another if you want to retain the face, but swap from 4 to 6 cyl.

For some photo references, go here:
https://www.fiero.nl/forum/A...031229-2-037230.html
Pay NO ATTENTION to all this adding capacitor nonsense in that thread.. it only matters if you are using a bigger engine, since you already HAVE the 4 cyl tach board, it just screws on.. follow these directions

Scroll down on that thread and you will see a pic of a tachometer removed from the cluster for reference. There are two silver cylinders on the back of the gauge that are screwed to the tach circuit board. The top is your tach, the bottom is your temp gauge. Remove the nuts off the back of the tach board that are attached to those screws coming from both the 2 silver cylinders. This will make the circuit board come loose from the gauges. Then simply put the new 120mph tach gauge silver cylinder on the old 4 cyl tach circuit board and attach the screws with the little nuts in the same place (reuse nuts) . Since you will be using the aux gauges, there is no need to worry about what you do about not having anything to attach to the bottom of the board (Your new tach will only have one silver cylinder on the back).. so where the old temp gauge used to hooked up on the circuit board just gets left empty.

Just attach the new gauge to the old tach board in the same position on top with the same screws . Attach it back to the gauge cluster and you are good to go.

Then of course, you will need to run the wires for your aux gauges since you are doing this to a car that is not "plug and play." (1986 and up have a wire harness already wired in for the aux gauges.) Follow the previously provided instructions to do that. here's that link again:
http://www.frontiernet.net/...tt/AuxGageInstal.htm

If you hit a snag, come back and tell us whats up!
Have fun, its EASY!

[This message has been edited by tbone42 (edited 12-08-2010).]

If there were a "few " Tachs "laying on the table" HOW can you tell a 4 cyl Tach fom a 6 cyl Tach ?? Thanks

quote Originally posted by Lou6t4gto: If there were a "few " Tachs "laying on the table" HOW can you tell a 4 cyl Tach fom a 6 cyl Tach ?? Thanks

Look at the gauge faces. V6 are different (pictured above). L4 pictured in the linked thread posted by Tbone.

[This message has been edited by Fieroseverywhere (edited 12-08-2010).]

It's been more than seven years after I posted that info, and to this day I still get the odd PM fired off to me asking about the tach modification. Good to see people still read the archives.

Anyone who refers to my pics will be able to see where the original capacitor is soldered in. You'll need to look at the number stamped on it. Here's what you'll find:

4-cylinder tach board: 0.01 uF
6-cylinder tach board: 0.0082 uF

Correct - you don't need to follow my "nonsense" regarding the actual modification if you have an original 4 or 6 cylinder engine. For clarity purposes, those values will be stamped on the capacitor itself, and NOT on the actual circuit board. Good luck!

While I rarely visit this site these days, I still own my V8 Fiero. I've owned this car for 8 years (almost 9), and have had some interesting experiences over the years.

I got it installed and everything works like it should except the temp gauge reads way past the red when it's warmed up, just like the old gauge did. I do have a new sensor but could it be the wrong one?