Question about 1991 Chevrolet Corvette

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Ignition Timing Following Top End rebuild, engine started. Went to check timing, engine runs well, timing mark on harmonic balancer not visible, turned distributor all the way to get mark in view, extrapolated to approx 14'BTDC, checked service manual, shut down, pulled four prong plug from distributer (per service manual) car would not start in order to time

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  • Anonymous Sep 05, 2008

    The answer given was not correct.the wire that you will disconect on a corvette will be a green wire that conects to a black wire on a tune port engine,Only a full size truck has a tan and black wire. and the timing is set at 6 DEG BTDC on the corvettte not TDC like the GM pickups with throttlebodies. The corvette dude.

  • Anonymous Mar 18, 2014




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How to check and adjust the timing
Disconnect the tan/black wire EST (electronic spark timing) by-pass connector located near the heater housing in the engine compartment on the S/T series, or near the distributor on all other V-6 models. Do not disconnect the four- (4) wire connector at distributor. Connect the timing light to the No. 1 spark plug wire. Check timing and adjust to "0" degrees BTDC. With the engine off, reconnect the EST by-pass connector and clear the ECM trouble codes by disconnecting the battery.

Posted on Aug 20, 2008


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