That about sums it up. Just how much would have to be done to the wiring? Also on the digital dash is the tach reading done by cable or by electronics as on the 91.

 

Which digital dash will you be using? '84 - '86 Berlinetta, '89 TA, Corvette, or aftermarket?

The digital dash units use electronic inputs for the speedo & the tach. The tach calibration is permanently programmed in PROM inside a microcontroller (Berlinetta), so make sure you get the correct version - V6, or V8, or the tach will be off by 25%. The GM speedos are calibrated for 4000 pulses per mile, so your 91 ECM speedo output will drive the cluster without the speed buffer, as was used with older version ECM setups. You will need the connector pinouts for your cluster and the new cluster, as well as a connector for the new cluster. I have the pinouts for the '90 - '92 cluster & the '84 - '86 Berlinetta cluster, if you need them.

Tim

 

It's out of an 86TA. My 91 wiring would probably be more difficult to put it in then an 88TA that came with analog guages. Am I correct in assuming that since GM offered both dashes in 86-88 that an analog dash is already wired for a digital dash and that it is just a matter or cutting the wires behind the guages and trying to match them to the digital wires. Probably not that simple but I can always hope.

 

I have converted the other way around - from the digital dash in an 85 Berlinetta to an 86 Cable driven dash from an 86Z. The dash from the Z was from an LG4 so there was not much difference in the firewall connector. (The wipers needed to be re-wired.)

In my swap, I found that that I had to replace the Entire dash housing, the entire heater/AC system, the steering column, the floor console, Ect. I also found that the wiring harness for the rear taillights were not the same and the berlinetta wiring had to be replaced with a Z28 harness from the tail-lights back to the fuse box. the speedo sending unit also had to be changed to a cable driven unit.

I'm not sure how similar the firebirds are - but in the camaro's it's night and day !

John in RI
Berlinetta@prodigy.net

 

I am no guru on this, but I would think that it would be a direct swap. For one, it wouldn't be very feasable for GM to create a whole new dash and wiring harness. I put a '91 cluster in my '87 and the only thing I swapped out was the oil/temp gauge b/c I didn't like the L/H insted of 0-60psi. It was a direct swap. I would go a head and swap them and see what happens, it is easy to do and you will know first hand what does and does not work. I think you will need the cluster bezel though. Just make sure the digital has the same two plugs that the analog one has.

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