on the 1992-96 the engines an LT1-4 and the CPU controlls the ignition, on the 1984-91 this info below should help)hook up the timing light to the battery and find the #1 plug wire
obviously an LT1 regulates its own ignition timing and uses knock sensor, and programable CPU input and the crank sensor unlike the L98 with it HEI but both system need you to check /verify they are operating correctly.
now
you just need to disconnect the black ignition connector back near the firewall
(center of picture) but on a corvette its long black and roughtly round like a fuze holder (but on the 1985 vette its located near the rear of the drivers side cylinder head)
watch this
http://www.youtube.com/watch?v=YdIGZ-tVuZA
watch video
http://www.youtube.com/watch?v=UYGU7mTw ... r_embedded
heres another description
http://www.aztpi.com/newsletters/NewsLetter-07-04-15.pdf
To set the timing on TPI and TBI
vehicles, first locate the timing
disconnect. This is a single wire
Weatherpack connector, typically on a
tan wire with a black stripe. On many of
the trucks, this can be found on the
passenger side of the firewall near the
relays but its location varies by vehicle
so you may need to consult a shop
manual. The Painless fuel injection
harnesses we sell for these vehicles
include this connector too. It’s normally
found about a foot from the ECM.
Once the connector is located,
disconnect it, causing the computer to
no longer control the timing. Connect a
timing light to the vehicle, start the
engine and set the timing in the usual
way. The ignition timing setting is
typically on the emissions sticker under
the hood or can also be found in a shop
manual.
Once the timing has been set,
reconnect the timing connector and
you’re done! By the way, it’s normal for
the check-engine light to come on while
the connector is disconnected. It will
turn off once the connector is
reconnected and the vehicle is restarted.
set the timing at 6 degrees btdc and reconnect the EST connector it should jump the timing to about 14 BTDC, , disconnect the timing light
viewtopic.php?f=70&t=875
viewtopic.php?f=70&t=840&p=2309#p2309
viewtopic.php?f=70&t=1443
obviously an LT1 regulates its own ignition timing and uses knock sensor, and programable CPU input and the crank sensor unlike the L98 with it HEI but both system need you to check /verify they are operating correctly.
now
you just need to disconnect the black ignition connector back near the firewall
watch this
http://www.youtube.com/watch?v=YdIGZ-tVuZA
watch video
http://www.youtube.com/watch?v=UYGU7mTw ... r_embedded
heres another description
http://www.aztpi.com/newsletters/NewsLetter-07-04-15.pdf
To set the timing on TPI and TBI
vehicles, first locate the timing
disconnect. This is a single wire
Weatherpack connector, typically on a
tan wire with a black stripe. On many of
the trucks, this can be found on the
passenger side of the firewall near the
relays but its location varies by vehicle
so you may need to consult a shop
manual. The Painless fuel injection
harnesses we sell for these vehicles
include this connector too. It’s normally
found about a foot from the ECM.
Once the connector is located,
disconnect it, causing the computer to
no longer control the timing. Connect a
timing light to the vehicle, start the
engine and set the timing in the usual
way. The ignition timing setting is
typically on the emissions sticker under
the hood or can also be found in a shop
manual.
Once the timing has been set,
reconnect the timing connector and
you’re done! By the way, it’s normal for
the check-engine light to come on while
the connector is disconnected. It will
turn off once the connector is
reconnected and the vehicle is restarted.
set the timing at 6 degrees btdc and reconnect the EST connector it should jump the timing to about 14 BTDC, , disconnect the timing light
viewtopic.php?f=70&t=875
viewtopic.php?f=70&t=840&p=2309#p2309
viewtopic.php?f=70&t=1443