87 5.7 Iroc. I'm adjusting the valves after a head gasket replacement project. First time doing this and I need a little clarification on something. I've got instructions on the process from this site(very helpful) in hand. When they state "on the exhaust stroke" does this mean when the exhaust valve is going to open or when it has just closed? I have observed that #1 is at top dead center when the exhaust valve on #1 closes. Is this the point where I make my adjustments or on the previous stroke right before the exhaust valve opens?

 

Turning the engine in the direction it runs:

Adjust the int on each cyl just as the exh for that cyl is just beginning to open; and adjust each cyl's exh just as its int returns to full closing after full opening.

Don't bother with the "put the engine here and adjust these, then put the engine there and adjust the rest" methods. They are nowhere near accurate enough.

The main thing to watch out for when using an accurate method, is your definition of "zero lash". This should be just when you can no longer move the push rod UP AND DOWN between the lifter and the rocker with your fingers; DO NOT bother with the "twist the push rod" mistake.

 

Thanks, that makes sense. It would appear the "put the engine here and adjust" method relies on additional preload to pick up the slack. With the method you laid out, 1/2 turn should do it.