Z28 Gauges in Roadmaster Wagon

You can get a tach out of the yard for that, CE.

 

My 82 Custom Cruiser has gauges, but they are very small and mostly hidden by the steering wheel. My speedo is 3 feet long and 2 to 7 mph off I found out on my trip to TN. (no ticket just the GPS telling me)

Does anybody know some option for my year/model? I was just going to build a custom dash at some point but if there is a ready to install option I might go with that.

 

I looked all over for a set of those small gauges for my '89 Custom Cruiser, but the late 80's wagons used lighter wood dash trim, and I never found a car with matching dash trim.

I like the little gauges, better them than nothing. My car only had the speedo and fuel gauges.

 

Went home at lunch and found my early Christmas gift on the front porch.

Gary did a great job adding the PRNDL and I like the white gauge needles as well.


I may try to use my old cluster's clear lens as this one has some hazing. It's not bad but I think the one in my car now is better. Also going to plug the unused hole that was for the Roady trip odometer. I still have a few Citation X-11 gauge clusters and when GM added the tach to those they pugged the lens hole for the clock adjustment rod with a little black button. Going to use one of those on the Roady lens.


I'm a little torn about changing all the bulbs. The PRNDL is going to light up the stock Roady blue/green color. I'm guessing the rest of the cluster would light up white. I know I could install blue bulbs in the cluster and that is supposed to "green it up", but have not decided if I want to have two different colors of green or just leave the main gauges white. Guess I'll pick up a set of blue bulbs and once it's all plugged in and dark make that decision.

The odometer is set to zero. Nothing like a fresh start!


Will update the thread when I get started on the install. I have to work this week so will be next week sometime before I tear into this. Can't wait! These gauges are SO SHARP!

Such fun,

-Mike

 

Ok....guess what I did last night? That was more work than I thought. Had to cut away some of the upper dash to get it all to line up.
Lets start on a positive note. It looks fantastic and after messing with it a bunch it all lines up well. Took the pics below with my cell phone camera when I got into work this morning, so sorry if they are a little blurry.




Now for the not so good...and I am somewhat bummed as I've wanted to do this mod since I bought the car.
Here's the deal. The oil gauge is not reading correctly. When fully cold, it only goes up halfway on the gauge, and when warm, it drops to nearly the red area at a stop in gear, and only goes up a bit when driving. I did swap out the sending unit with the one that came with the cluster. I'm hoping there is another sending unit option I can go pick up to correct this.
Pic is of the car in gear with a warm engine:

Then there is the temp gauge, which seems to read too high. On the old Roady cluster, which was just a Cold/Hot gauge, my needle never went over half way. With this cluster, it reads well over half way when warmed up. It never goes to the red, but sure reads higher than it ever did on the stock cluster...and it was only 45-degrees this morning.
This was taken in gear, at idle, after driving 5-miles to work this morning:

Lastly, I think the tach may be off. I'm worndering if, being a '96 model with OBDII, if the signal is wrong. At cold start it goes to 1000rpm and then reads 800rpm in gear. In normal driving it shifts just under 2K rpm and I got on it once and it never went above 2800 rpm before shifting. At 70mph it's reading 1800rpm. I've not done the trick with checking the gauge against the digital readout using the climate control screen. Honestly after all the expense of this, and all the work it took to install, I was pretty down in the dumps last night.
On a positive note, the PRNDL looks and works perfect. All the gauge lights work, signals, high beam, seat belt, security, all work just as they should. I had put blue bulbs in at first but didn't like the look so went back to white before buttoning it all up.
The speedo reads perfect, I ran it against my Garmin. Fuel gauge seems to be fine, and both the regular and trip odometers work fine. My car has 18 miles on it as I type this now.
So that's it. If anyone has ideas on why the gauges read what they do, I'd love to hear them. I for sure want to/have to fix the oil gauge....reading just above red is already driving me nuts.
I suppose the temp gauge could be correct....maybe it's the difference of going from just a hot/cold gauge to one that is based on an actual number. It never gets up to the red...it just seems high.
As for the tach....I have no idea, but it sure seems like it should be in the 2000's before shifting, especially when pulling into traffic. It sure sounds like the engine is going faster than what it's reading.
Arrghh... I'm know I'm crazy, but I was really looking forward to having this, and now that I do, it does not seem to work right....
-Mike

 

The temp gauge looks like it may be correct to me.
OK...the oil pressure gauge has been problematic on these cars.
FIRST: try both available sending units....disregard that one is for a light and one is for a gauge. If that does not work....
SECOND: you will have to do the "fix" by finding the correct wire in the harness up behind the glove box and bypassing the resistor in that wire. Not as bad as it sounds. Here is a thread that will help. There are others there, too. They have pictorials so it should be a cake walk.

http://www.impalassforum.com/vBulletin/showthread.php?t=227401

 

I didn't read the entire Impala forum thread but I would think it would be wise to start by temporarily hooking up a good mechanical oil pressure gauge and note readings at various rpm to use as a benchmark for 'calibrating' the in-dash gauge with a resistor or different sending unit. otherwise, how do you know what your shooting for?

 

The Roadmasters do not have a resistor like the Caprice's do. I'm glad because I hate wiring. Funny thing, I was told to go pick up a 60psi oil sending unit from a pickup and replace the one I got, which is an 80psi meant for a 9C1 police Caprice. I may give that a shot.

-Mike

 

It almost looks like 750 rpm in the pic, thats not to far off from what it should be. Also how deep into the throttle were you when it changed gears? Like they said borrow a guage or in this case a stand alone tach to find the base line.

I think it looks great by the way. Easy to read. I like it.

Keep at it, it wont take long.

 

I love the looks of your instruments!! Would love to have someone do this to my -72 cluster!

 

Yes...do that. The Cappy fix is to do both. I would then think that, since, as you say, the Roady doesn't have the resistor problem, the truck unit would work. That's my thinking, anyway.

 

Actually it looks like I may just be living with this. Been looking around and 6-8 PSI is considered normal for an LT1 at warm idle. Sure sounds low to me, but looks like the gauge is working.

I'll just have to get used to it I guess.

-Mike

 

Well...I have the stock gauge in my Cappy ... never did the mods, but, I tested it and the pressure (new engine) was 40 to 60. The stock gauge is showing the usual...just above the red zone and crawls up a tiny bit under high RPM's. Everything slightly higher when the engine is cold.
I would sure try the truck sending unit. Easy to swap and may solve the problem.

 

Just got REALLY done with my Z28 cluster install in my Roadmaster wagon. Want to thank Gary very much for all the help. He got right back to me and answered all my questions, and is helpful and great to work with.

I had that issue with the oil pressure gauge reading too low when I first installed my cluster. It caused some frustration but the fix was easy. Originally I installed an O'Reilly aftermaket sending unit for a 9C1 Caprice. I swapped that for a Delco sender for a '96 Z28 and it fixed the problem. Sender was $45, so a little pricey, but well worth it. Make sure to pick up a sender socket as well, about $10 at most parts stores.



Oil Pressure is FINE now!


Before the mod....Bye-Bye Granpa!



A couple other good things to know. The temp gauge gets it's signal from a different location on the engine than the readout on the climate control when in diagnostic mode. In my case the gauge reads a little higher, but that's just because of where it gets it's signal.

A really good upgrade is to swap the Z28 bulbs for 194 bulbs. The Z28 cluster is dimmer than the Roady cluster. Putting the 194 bulbs from the old Roady cluster made the Z-cluster much brighter.

Roadmaster gauges are backlit blue/green, and the Z-cluster is white...unless you get the PRNDL option, which lights up blue/green. I tried adding 194B (blue bulbs) first but it just looked wrong, so I went back to the clear white bulbs. It looks odd the first time you drive at night but after 5-mins you'll be used to it.

The dash panel behind the cluster does need a good bit of trimming to get the cluster to sit correctly, but Gary builds the Roady units using older Roadmaster clusters, so the mounting points are all the same, and once the dash is trimmed correctly, it sits perfect and for all the world looks factory.

This is a great mod and well worth the effort!

-Mike

 

You can put the car in diagnostic mode using the digital climate control, and it gives you readouts for temp and such. One of the readouts is a digital tachometer. I compared it and it matched the new gauge, so the tach worry was just me being used to watching the tach dance in my wife's V6 Grand Prix. The tach works fine in the Z-cluster.

I'm loving this mod now that it's sorted out.

-Mike