Some of you might be aware that I am doing another L67 swap but this time it is into a 1989 Buick Reatta. (you can follow the build thread on http://www.l67swap.com forums)
Well it just so happens the owner of this particular Reatta has expressed interest in swapping in a 92 Riviera digital cluster instead of his anemic digital stocker. Here is what the Riviera cluster looks like:
The GOOD news is it appears this cluster my physically fit within the confines of the OEM Fiero gauge pod without too much trouble. As soon as I get ahold of one of these things I will measure it up and let you all know.
The BAD news: Well, this cluster requires a BCM to provide it with most of the guage and warning light information. However, the BCM wiring indicates to me that it could be made to work in a Fiero. The only bad thing is that it appears the cluster itself requires an uplink with the 3800 computer via serial data line in order to operate the tachometer. I am pretty sure the stock Fiero ECM is not capable of providing the correct signal but those of you with engine swaps using an OBDI computer might be able to use it. Again, I will know more once I have one here and play with it a little.
------------------ power corrupts. absolute power corrupts absolutely. Custom Chip Burning | Fiero Engine Conversions | Turbocharging | www.gmtuners.com
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07:33 PM
PFF
System Bot
Dec 8th, 2004
1MohrFiero Member
Posts: 4363 From: Paducah, Ky Registered: Apr 2003
I have though about that , but never got around to pursuing it. I LOVE the digital gauges, and those Reatta ones look very similar to the International Cutlass.
Please keep us updated on that... I am VERY interested!!!!
Arghh. That's what I get for being a slacker.. Beat to the punch.
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Originally posted by Darth Fiero:
The GOOD news is it appears this cluster my physically fit within the confines of the OEM Fiero gauge pod without too much trouble. As soon as I get ahold of one of these things I will measure it up and let you all know.
Yep, it's very close. A little trimming on the Fiero gauge pod bracket and a little trimming of the Reatta cluster is all it takes. Most of the interference is in the steering column hump and where the connectors plug into the Reatta cluster. I can provide some pics of the clearancing required to the pod if you like. For the Fiero, you'll need to build a new faceplate for it. Here's a pic from my Archie dash buildup thread, you can just barely make out the cluster. It doesn't show much and I had to trim off the switch areas for the dash I was using, but it shows some of the back trimming.
quote
The BAD news: Well, this cluster requires a BCM to provide it with most of the guage and warning light information. However, the BCM wiring indicates to me that it could be made to work in a Fiero. The only bad thing is that it appears the cluster itself requires an uplink with the 3800 computer via serial data line in order to operate the tachometer. I am pretty sure the stock Fiero ECM is not capable of providing the correct signal but those of you with engine swaps using an OBDI computer might be able to use it. Again, I will know more once I have one here and play with it a little.
99% of the wiring is very easy and the only tricky part was as you said, the tach. On the schematic I'm using, one of the pins is labelled coil or crank, I can't remember which at the moment. I assume this one is for the tach signal and it is available by splicing into the IM harness. I wanted to do some more research on this one, it seemed odd that the BCM would want access to that circuit. IIRC, the serial data line is only needed for the MIL and likely some functions that are no longer being used (at least in my setup). I wonder if the missing functions in the BCM are going to throw the MIL on the dash for non-engine related errors.
I'm talking off the top of my head now, my diagrams are not with me right now. Keep up the good work, Darth, I'm sure this one will be as cool as the rest of them.
[This message has been edited by Stinkin_V8 (edited 12-08-2004).]
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10:21 AM
intlcutlass Member
Posts: 1431 From: Cleveland,Oh.44067 Registered: Nov 2002
Originally posted by Stinkin_V8: 99% of the wiring is very easy and the only tricky part was as you said, the tach.
Thats the reason you can't put a 3800 II in a Cutlass Supreme with a digital tach and have a working tach. The W-Body guy Shawn Lin explained it to me once, but the most I can remember right now, is that you would have to piggy back the computers.....
Thats the reason you can't put a 3800 II in a Cutlass Supreme with a digital tach and have a working tach. The W-Body guy Shawn Lin explained it to me once, but the most I can remember right now, is that you would have to piggy back the computers.....
That is plan B for me - running a second ECM to handle the BCM/cluster. Then I'm back to the MIL issue - which one lights it? This might not be a point of concern - now that I think of it, the SES may be down in the bulb-lighted display near the bottom. Like I said, I gotta check my scem's.
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11:23 AM
Darth Fiero Member
Posts: 5921 From: Waterloo, Indiana Registered: Oct 2002
Thats the reason you can't put a 3800 II in a Cutlass Supreme with a digital tach and have a working tach. The W-Body guy Shawn Lin explained it to me once, but the most I can remember right now, is that you would have to piggy back the computers.....
We know that OBDII computer data streams are completely different than OBDI data streams which is why the digital cluster's tach won't work. And BTW, I have 2 of those Cutlass digital clusters and wish they would fit in a Fiero but they are just too long. For this project I will be using a 95 Bonneville 3800SC OBDI computer to control the Series II engine using one of my custom chips. There is a parameter in the stock 95 OBDI computer program that when switched on tells the PCM to send data to other modules that exist on in the car via the serial data line. Within a couple of weeks I will be able to determine if this signal is compatible with the earlier Reatta electronics or the 92 Riviera stuff.
Darth, you probably already know that the BCM data stream spec is included in the ALDLStuff.zip from diy-efi as A146.DS and A180.DS. It's over my head but just in case you didn't know about it, maybe it would be useful. I can email 'em if you like.
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01:41 PM
intlcutlass Member
Posts: 1431 From: Cleveland,Oh.44067 Registered: Nov 2002
We know that OBDII computer data streams are completely different than OBDI data streams which is why the digital cluster's tach won't work. And BTW, I have 2 of those Cutlass digital clusters and wish they would fit in a Fiero but they are just too long. For this project I will be using a 95 Bonneville 3800SC OBDI computer to control the Series II engine using one of my custom chips. There is a parameter in the stock 95 OBDI computer program that when switched on tells the PCM to send data to other modules that exist on in the car via the serial data line. Within a couple of weeks I will be able to determine if this signal is compatible with the earlier Reatta electronics or the 92 Riviera stuff.
So your gunna use a Series II engine , with Series I electronics, so you can use the digital cluster....Good call!!!
Looking at my schematics now.. The IP harness consists mostly of grounds, power, UART, signal lights and some other non-engine related stuff. The SES/MIL is a seperate wire so it can be run to the ECM. The BCM looks like it takes feeds directly from the engine sensors and what what I think looks like the tach signal is at BC14 is ckt# 806, labelled "crank". Of course, I don't have any of my other diagrams in front of me at the moment so I can't cross-reference this circuit. It looks like this one is the only questionable hookup but I'd be willing to bet that this is either the 3x or the 18x signal from the crank sensor.
It doesn't look to me like the BCM really needs the ECM in order to run the dash. Hope this helps. On second thought, I hope this leads you so astray that it takes you months to complete and then I can be first. Just kidding. After all the help Darth has given me, I hope this is a little in the way of repayment.
Darth or Intlcutlass - can you get me a dimension of the Cutlass cluster? While the Riv/Reatta cluster fits great in the stock Fiero gauge pod, it's almost too narrow for the Archie dash.
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08:53 PM
Darth Fiero Member
Posts: 5921 From: Waterloo, Indiana Registered: Oct 2002
The BCM looks like it takes feeds directly from the engine sensors and what what I think looks like the tach signal is at BC14 is ckt# 806, labelled "crank". Of course, I don't have any of my other diagrams in front of me at the moment so I can't cross-reference this circuit. It looks like this one is the only questionable hookup but I'd be willing to bet that this is either the 3x or the 18x signal from the crank sensor.
According to my info ckt 806 gets power via the 3amp Crank fuse only during engine start (crank). So this would not be the tach feed. I speculated that the Riviera cluster gets tach data from the PCM Serial Data Line because the same holds true for the Cutlass Supreme digital cluster.
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It doesn't look to me like the BCM really needs the ECM in order to run the dash. Hope this helps. On second thought, I hope this leads you so astray that it takes you months to complete and then I can be first. Just kidding. After all the help Darth has given me, I hope this is a little in the way of repayment.
Darth or Intlcutlass - can you get me a dimension of the Cutlass cluster? While the Riv/Reatta cluster fits great in the stock Fiero gauge pod, it's almost too narrow for the Archie dash.
You are correct in that it appears the BCM needs no data from the PCM in order to run the cluster which leaves the only inputs that the cluster needs is for the speedo (via VSS wire) and Tach (via serial data line). I will get some measurements and a pic of the cutty cluster when I can dig it out. Might be Christmas until I can get to it though.
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09:52 PM
PFF
System Bot
Dec 11th, 2004
formulagator Member
Posts: 53 From: Ocala,FL. USA Registered: Feb 2004
If anyone wants to try this I can get one of these clusters out of a 91 Cutlass w/ 3.4 dohc. I can get the connector and some of the harness too. About $60.00 shipped but I can't guarantee it, it is from a totaled car though. I may use it for my 3800 Sc if no body wants it. Rich
------------------ Rick Longfellow Formulagator fierorick64@earthlink.net rlongfel@ufl.edu 88 Formula 3800 SC 5 speed 84 SE 2002 2.2L 5 speed 85 GT 3.1 Auto
I have a 92 Cutlass International digital dash working with the 92- 95 3800 ECM's. Too bad it's so long. I wanted to put it in my Ciera SC but it won't fit. Well, not without some major work.
Nice dash though.
[This message has been edited by TK (edited 12-13-2004).]
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12:13 AM
Darth Fiero Member
Posts: 5921 From: Waterloo, Indiana Registered: Oct 2002
I have a 92 Cutlass International digital dash working with the 92- 95 3800 ECM's. Too bad it's so long. I wanted to put it in my Ciera SC but it won't fit. Well, not without some major work.
Nice dash though.
So what you are saying is the tach on the digital cutlass cluster works with the 94-95 16183247 3800 computer? If so I will be VERY happy.
No, the data fields in one of the scheduled messages have to be modified for 92-93 (ID, length, etc.)
I originallly changed two messages to get the 88-91 DIC to work with the 92-93 ECM. From that I got the dash to work.
The 94-95 messages are pretty close for the Cutlass dash. I'd have to pull my notes and code to see if I touched it very much. But it shouldn't be a problem for you.
Just check the message ID and length and make sure the RPM is in the same location as the dash requires.
[This message has been edited by TK (edited 12-13-2004).]
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10:03 AM
Darth Fiero Member
Posts: 5921 From: Waterloo, Indiana Registered: Oct 2002
No, the data fields in one of the scheduled messages have to be modified for 92-93 (ID, length, etc.)
I originallly changed two messages to get the 88-91 DIC to work with the 92-93 ECM. From that I got the dash to work.
The 94-95 messages are pretty close for the Cutlass dash. I'd have to pull my notes and code to see if I touched it very much. But it shouldn't be a problem for you.
Just check the message ID and length and make sure the RPM is in the same location as the dash requires.
I have an incomplete disassembly of the $5B code and I remember seeing something in it that related to ALDL data stream schedules and what not. If you could supply me with the cutty dash address requirements it would be MUCH appreciated. Only thing I wish I had now was a disassembly of the 88-91 3800 ECM so I could see where the data is scheduled in that, maybe then I could get the 94-95 $5B PCM to work for sure with the 89 Reatta CRT and BCM. Any ideas where these other disassemblies might be floating around?
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03:19 PM
Dec 14th, 2004
Fieroking Member
Posts: 2144 From: Coeur D Alene Idaho USA Registered: Jun 2002
How about using one of these dashs with a 91 Caddy 4.9 ECM? I am so looking for a Digital Dash for my 88 Formula/GT 4.9.
Joe Sokol
------------------ 85 SE 2.8 - beater coupe- 86 SE 3.4 -in progress 3800 II SC - 88 Formula GT 4.9 5 speed beast Enough parts outside for another one -And a 3.4 push rod for sale in the mall Go and look-
This is what I have, there are more tables but these appear to be what we need to be concerned about. Now all I need to know is IF anything needs to be changed, and if so, where and what to change it to.
I originally changed MSG2 in the 92/93 code to run the earlier DIC (gauges, MPG, range, etc.) That required a double byte RPM. Funny, if you plug that DIC into stock code, the DIC reads DIAGNOSTICS.
In hindsight though, I tried the Cutlass dash after I modified the message for the DIC. I'm thinking now that MSG1 might be what is read by the dash and not MSG 2. MSG1 in the 94/95 ECM might work without changes.
If it doesn't then MSG2 will need to be changed in the order with a message length of 10. The order of MSG2 is different in the 94/95 from the 92/93.
The problem is that I only knew what the 90 3800 ECM was sending to DIC and I was concentrating on that. I didn't know specifically what message the dash was reading. I started to disassembly the DIC code but it's an weird processor and I never went very far. I had plans to make it act as an ALDL scanner. Project 4562.....
As I said, it's possible the dash is reading MSG1. If so, it might work without changes. The Rivera dash might read the same message too. Try it. If it doesn't, the order I listed above should work. Otherwise I will have to work more on the message scheduler for the 4.9L code. I haven't gone into that area.
Keep me posted. Power, ground and ALDL should be all you need to test the dash. If the tach works, you got it.
I assume I get royalties for this......
TK
[This message has been edited by TK (edited 12-14-2004).]
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10:34 PM
Dec 15th, 2004
Darth Fiero Member
Posts: 5921 From: Waterloo, Indiana Registered: Oct 2002
Replaced the CRT with a good one and turned the key on. Got an error for no communication with ECM. Tried 3 different .bin files all from different cars (95 Riviera, 94 C-car, 94 H-car) to no avail. Will need to know more about 89-90 Reatta BCM-PCM communications and see if I can get this working. However, the owner has expressed his dislike for the current dash/cluster and the fact that he wants a CD player so he is thinking of upgrading to the Riviera cluster and HVAC controls anyway. I got the cutlass digital cluster sitting here I might go out and hook it up to see if the tach will work.
Anyway if anyone can help I am looking for info on the message scheduler / data stream for ECM to BCM communications on the 89-90 Reatta. I would still like to see if we could get this thing figured out. Any help would be appreciated.
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10:05 PM
Darth Fiero Member
Posts: 5921 From: Waterloo, Indiana Registered: Oct 2002
Got some pics of the Cutlass Supreme Digital Instrument Cluster TK was talking about.
It measures 18.25" wide, 6.75" tall, and 2.875" thick overall. The actual digital display measures 11.125" wide and 2.125" tall. This cluster does NOT require a BCM but does require ECM/PCM serial data link and the correct program message interface instructions to operate the tachometer.
