Ign Timing and Valve Adjustment on '88 5.0 Corporate Eng

[DanC]

I'm new to this "corporate world" and have a couple questions. '89 Firebird Formula with an '88 5.0 (305) engine.

1) Ignition Timing Adjustment: The "VECI" label on the hood and the Clymer manual I have both state disconnect the single wire timing connector. A tan wire that breaks out of the wire harness. The only single wire connector I find is a white wire and it kills the in dash tach.

Is this the bypass wire for timing?

Right now it does not effect the mark position connected or not.


2) I adjusted the valves according to Clymer. Rotate pushrod between fingers until zero lash then tighten one full turn. Well I ended up with an engine that would not start http://forums.performanceyears.com/groupee_common/emoticons/icon_confused.gif Also had zero compression http://forums.performanceyears.com/groupee_common/emoticons/icon_mad.gif I backed off the rocker nuts 3/4 turn and got compression and an engine that runs, but poor and rough.

The procedure was #1 firing position adjust 1, 3, 4, & 8 exhaust. 1, 2, 5, & 7 intake. Rotate 180deg adjust 2, 5, 6, & 7 exhaust. 3, 4, 6, & 8 intake. This is a roller cam I believe as the lifters have two flat sides to prevent rotating.

What is the correct proceedure for adjusting the valves?

Thank you for any input,
DanC

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I'd rather be Historically Accurate than Politically Correct !

[This message was edited by DanC on January 26, 2004 at 03:12 AM.]

[DanC]

I'm new to this "corporate world" and have a couple questions. '89 Firebird Formula with an '88 5.0 (305) engine.

1) Ignition Timing Adjustment: The "VECI" label on the hood and the Clymer manual I have both state disconnect the single wire timing connector. A tan wire that breaks out of the wire harness. The only single wire connector I find is a white wire and it kills the in dash tach.

Is this the bypass wire for timing?

Right now it does not effect the mark position connected or not.


2) I adjusted the valves according to Clymer. Rotate pushrod between fingers until zero lash then tighten one full turn. Well I ended up with an engine that would not start http://forums.performanceyears.com/groupee_common/emoticons/icon_confused.gif Also had zero compression http://forums.performanceyears.com/groupee_common/emoticons/icon_mad.gif I backed off the rocker nuts 3/4 turn and got compression and an engine that runs, but poor and rough.

The procedure was #1 firing position adjust 1, 3, 4, & 8 exhaust. 1, 2, 5, & 7 intake. Rotate 180deg adjust 2, 5, 6, & 7 exhaust. 3, 4, 6, & 8 intake. This is a roller cam I believe as the lifters have two flat sides to prevent rotating.

What is the correct proceedure for adjusting the valves?

Thank you for any input,
DanC

------------------------------
I'd rather be Historically Accurate than Politically Correct !

[This message was edited by DanC on January 26, 2004 at 03:12 AM.]

[DanC]

1) Okay, I found the tan/black wire. It was not where it was suppose to be, behind the RH valve cover. It was under the RH hood hinge! Got the timing set and idle down http://forums.performanceyears.com/groupee_common/emoticons/icon_smile.gif

2) I loosened all the rocker nuts and the engine started. Then did the ole tapping noise, tighten till it stops thing. Found out that any more than about an additional 6th of a turn after no tapping caused the engine to die.

Curse you corporate GM http://pysales.com/images/evil.gif!!!!!!!!

I'm still kinda interested on how the adjustment is suppose to be done.

Runs great now!

DanC http://forums.performanceyears.com/groupee_common/emoticons/icon_biggrin.gif

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I'd rather be Historically Accurate than Politically Correct !

[Ken French]

Dan, the adjustment you wrote down is correct. Although, I personally preload the lifters to 3/4 turn after 0 lash. The problem that I believe you encountered is: sometimes on a non pumped-up lifter, it is very hard to find 0 lash. With the lifter not filled with oil, it starts to collapse, and while you're rotating the pushrod to feel 0 lash, you're actually turning the inside of the lifter as well. You should start all over again, especially now, because the lifters are full of oil, and will be easier to feel. If you use a flashlight, and maybe even a mirror, to look down to the pushrod & lifter, you can better see true 0 lash. Hope this makes sense. Ken