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Carb'd 91

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Old 09-29-2014, 11:06 AM
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Engine: D17A2, L31 based sbc, LS1, LM7
Transmission: 5 spd, built 700r4, T-56, 4L60e
Axle/Gears: 4.11, 3.73, 3.42, 4.56
Carb'd 91

Searched but couldn't quite find what I'm looking for...

Car is a 91, originally a 3.1 Now sporting a mild 400+ hp/tq SBC. The trans is out of an '88 TBI car. ECM, SIR/Air bag sys has all been eliminated etc. I have the Red nylon gears & the purple & yellow wiring harness bagged up in case I needed it. The 700r4 (at the moment) I believe has the Blue nylon gears in it at the moment.

Is it possible At all to make the current dash/speedo work for the car? Would running power via the purple wire compensate for a voltage source that the ECM once provided??

Is this possible, or would I have to switch to the earlier cable driven configuration w/ the older 82-89 (analog?) Gauges?...
Old 09-29-2014, 03:33 PM
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Re: Carb'd 91

Just need the 4-OUT BUFFER box that the 90 - '92 TBI cars used, the pre '90 Firebirds with the electronic speedometer also used that box. Along with Caprice TBI cars.

The box buffers the magnetic VSS and generates 2K and 4K PPM streams for the ECM and cruise control.

RBob.
Old 09-29-2014, 03:49 PM
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Engine: D17A2, L31 based sbc, LS1, LM7
Transmission: 5 spd, built 700r4, T-56, 4L60e
Axle/Gears: 4.11, 3.73, 3.42, 4.56
Re: Carb'd 91

So I still need the buffer box despite the fact that the ECM is no longer even in the car? & what do I do, run a power source(hot off the ignition) into the box & a ground?
Old 09-30-2014, 08:27 PM
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Re: Carb'd 91

The buffer box converts the VSS signal to something that the speedometer and CC can use. Originally the ECM for the 3.1l engine did this.

Needs IGN+, ground, two input wires from the VSS, and an output for each: speedometer and CC.

RBob.
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