Will the speedometer from my '85 z28 fit, and work, in the gauge panel of an '84 z28? I want the gauge panel from the '84 because the car had a 5.0 H.O., and it has the higher redline, and my stock temp gauge doesn't work, but I want to keep my stock speedometer because I don't like the dual pointer speedometer, and I want to keep my original odometer.

Also, is there anything else worth taking from the '84 z28?, it's in a junkyard. It originally had a 5.0 H.O., but all engine components are gone...

I just found it yesterday, and I already took the aluminum brake drums, and the 5.0 Liter H.O. dash badge.

 

I used to sell 145 clusters with some regularity. Sometimes they'd work well when swapped in, sometimes there'd be electrical issues. I finally recommended that if the the cluster currently in the car functioned as designed, to simply swap the speedo in, not the entire cluster. You could do the same with the tach and temp gauge (check the font on the 84 gauges as it may not be the same as the one on your 85).

Recently I found this from John in RI: "There are differences in the 82-89 clusters,....... If you use one from an 82-84 in your 87 than there will be a problem with the E-Brake warning light and one of the cluster "backlights". The above would account for the electric issues I mentioned.

JamesC

 

Here's a pic to show what Jim Described:



( I know the speedometer is not an 84 speedo - but that's not relevant here ! )

This CLUSTER and printed circuit is from an 84 and installed in a 86 IROC. The E-Brake warning light on the 82-84 clusters is on the far LEFT ( rather than the far RIGHT from 85-89.) You can see that when the backlighting is turned on the backlight behind the speedo on that side doesn't work. The issue is that the 82-84 printed circuit isn't completely compatable with the 85-89 Cluster plugs.

Swapping JUST the speedometer will NOT be a problem for Ya' !

Hope that helps explain it !

 

Actually, I want to swap everything except the speedometer, from an '84 to my '85. So... I could just take the gauges I want, which is the tach, oil pressure gauge, and temp gauge, from the '84 cluster, and put them in my '85 cluster?.
I'll give it a try!

 

The important thing is the Cluster & Printed Circuit. Be sure to re-use your original cluster / printed circuit and install what ever gauges/speedo you like the best. The cluster has to match the harness - the gauges don't care what cluster they are plugged into !

I prefer the 83-84 style gauges over all other styles too. I don't care for the double needle speedo however ! About 2 weeks ago I got lucky and found an HO dash clustermtself. It's got the 55000RPM tach, 18 miles on the odometer and the lens was crystal clear ! ( car had 118K for mileage )

 

I swapped my OE speedo for a 145 and the tack to the 5500. Plug and play.

JamesC

 

Ok, so now I got the swap all done. I used my stock cluster, printed circuit, and speedometer, but took all the other gauges from the '84. My temp gauge still doesn't work, so I guess I need to replace the sending unit, (Napa must have given me the wrong one, because before I replaced the sending unit it read about 30* cold, after it didn't work at all), I now have a consistantly working oil pressure gauge, but it jumps in about 3 psi increments, and the 'new' tach reads about 300 rpm high at idle, and reads 6000 rpm at about 4500 rpm. But, just like before, I have a good working speedometer and volts gauge!

This project was very quick and went very easily, but the final product was a disaster...

 

Sounds like the bugs *MIGHT* be on the printed circuit. This is a true story: I'm converting a Firebird from auto to stick right now. I also upgraded from cable to electric speedo. When I first got the cluster installed I had problems with a couple gauges. The first thing I did was looked at the engine sensors - wrong !

My problem was the printed circuit. When I pulled it out a couple days ago I found a burnt circuit that was causing the falier. I had to pull all the gauges OUT of that cluster and place them into another cluster. I just wrapped it up a couple days ago - true story.

Tachs are notorious for being wrong. V6 oil pressure gauges are 40/80 ( V6 Tach ) and V8 oil pressure guages are 30/60 ( V8 Tach )

Keep at it ! You will find the bug !!

 

Is the printed circuit on the back of the cluster raplaceable? I didn't look at it too closely while it was out...

Or do I have to replace the whole cluster?

 

By the way, the E-brake warning light on my '85 is on the far right...

 

Greg - THANK YOU ! I edited my original post to be correct ! You might think about editing or removing my quote in your earlier post so as not to confuse other readers that find this thread !

(E-Brake on 82-84 clusters is on the LEFT. E-Brake on 85-89 clusters is on the RIGHT !)


Thanx for catching my mistake !

P.S. You can replace the printed circuit - just be sure it's from a 85-89 car WITH gauges so it matches your harness. It's always easier to just install the gauges you like in a working cluster rather than swapping printed circuits. Chances are you can find a complete gauge cluster from a V6 car pretty cheap. (you could use any gauge cluster printed circuit from 85-89 - if you have a carb you migh loose the "CHOKE" indicator if the cluster is from an 88-89 )

 

That sounds like how a V6 tach would read.

 

Maybe, except for the fact that I took this tach because it came from a car with a 5.0L H.O.

 

On the cluster I took from the '84, the E-brake light is on the right side, just like my '85. I would post pics, but I keep braking my cell phones...
Tomorrow I'll go to the JY and get a cluster from an '85, there's a sport coupe in there I can take it from.
Unfortunately there's no Chevrolet dealer near where I live, to see if I could get a new printed circuit.
I'll be putting my original tach back in, but I might try and see if I can play with the resistors on the '84 tach to see if I can make it read right, since it's already messed up anyways.

Does anyone have a H.O. tach for sale? I'd still like to have one, but I couldn't even find one on ebay.

 

The 5500 red line doesn't have to be from an L69; IIRC, I picked mine up from a TPI IROC.

JamesC

 

Interesting... Now I have two junkyards to go to today.

 

I finallly had the time today to change out my cluster and tach, and I'm right back where I started before this whole project. Same gauges, and my oil pressure gauge still doesn't always work, and my temp gauge still doesn't work at all. Don't know what to do now... I even changed the connector on the oil pressure seding unit, thinking a bad connection might be the problem. Oh well, maybe I'll just get an aftermarket temp gauge and oil pressure gauge.

Another question, do I need to change the drive gear for my speedo cable if I change my speedo to a 115 or 145 mph speedo?

 

No.

JamesC

 

Alright, thanks!