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Old 10-09-2010, 11:45 AM
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Quote:
Originally Posted by Caballerokid
I did some searching on here for a refresher since I haven't done this in such a long time. normally i adjust each cylinder individually and thought about trying to go the quick way this time. Does this information sound right for a sbc?

"Starting with #1 and bring #1 up to tdc then do these vavles exhaust 1,3,4,8 intake 1, 2 5 ,7 rotate the crank one full revolution untill the timing pointer is on O at the crank shaft.... with #6th cylinder firing psition. Now do these valves exhaust 2,5,6,7 intake 3,4,6,8."
If the cam is a stock-type grind i.e. not a lot of duration, you can do it this way, it's called the "TDC Method" by some. The problems arise if the cam has any lifters up on the clearance ramps instead of all the way on the heel of the cam.

With performance engines, most will opt for the "EO/IC Method (Exhaust Opening/Intake Closing)" method, the way I have shown previously (originally from Crane, IIRC):

In order to adjust the preload, the lifter must be properly located on the base circle or "Heel" of the lobe.

At this position the valve is closed and there is no lift taking place. You will need to watch the movement of the valves to determine which lifter is properly positioned for adjusting.

1. Remove the valve covers, and pick a cylinder that you are going to set the preload on.

2. Hand rotate the engine in its normal direction of rotation and watch the exhaust valve on that particular cylinder. When the exhaust valve begins to open, stop and adjust that cylinder's intake rocker arm. (Why? Because when the exhaust valve is just beginning to open, the intake lifter will be on the base circle of the lobe, the correct position for adjusting the intake.)

3. Back off the intake rocker arm adjuster and remove any tension from the pushrod. Wait a minute or two for that hydraulic lifter to return to a neutral position. The spring inside the lifter will move the pushrod seat up against the retaining lock if you give it time to do so. (If you are installing brand new lifters they will be in the neutral position when they come in the box.)

4. Now spin the intake pushrod with your fingers while tightening down the rocker arm. (If you are uncertain that you are feeling the "Zero" setting, jiggling the push rod up and down will sometimes give a better sense of when all the clearance has been removed.) When you feel a slight resistance to the turning of the pushrod, you are at "Zero Lash". Turn the adjusting nut down one half to one full turn from that point. Lock the adjuster into position. The intake is now adjusted properly.

5. Continue to hand turn the engine, watching that same intake. It will go to full open and then begin to close.When it is almost closed, stop and adjust the exhaust rocker arm on that particular cylinder. (Again, when we see the intake almost closed, we are sure that exhaust lifter is on the base circle of the lobe.) Loosen the exhaust rocker arm and follow the same procedure described before in steps 3 and 4 to adjust this rocker arm.

6. Both valves on this cylinder are now adjusted, and you can move on to your next cylinder and follow the same procedure again.
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